----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------Important Questions for 2017 Public Examinations in AP Physics Important Questions 1 MARKS QUESTIONS 1. What happens to the water when wet clothes dry? When wet clothes are dried, the water present in the cloths changes to vapour state and mixed with air. 2. Covert 200C into Kelvin scale? Temperature in Kelvin =273 + Temperature in Celsius degrees. 20oC =273+20 =293 K 3. Define dew and fog? Dew:- The water droplets condensed on surface like windows, flowers and grass are known as dew. Fog:- Thick mist is called as fog. 4. Explain why dog pant during hot summer days using the concept of evaporation? 1. Dogs pants on hot days because they are trying to cool down just like we sweat on a hot days. 2. So, dogs pant to regulate their body temperature. 5. Equal amounts of water are kept in a cap and in a dish. Which will evaporate faster? Why? 1. Evaporation depends on the surface area. 2. Hence, the water kept in dish will evaporate faster than the cap. 6. Why does ice floats on water? The density of ice is less than the water. So ice floats on water. 7. Why the bottom of the cooking vessels are coated with copper? 1. Copper is a good conductor of heat and distribute the heat entire the vessel. 2. So copper bottom vessel is used for cooking. Thus it helps in cooking food quickly. 8. What do you know about the terms given below related to spherical mirrors? a). Pole b) Centre of curvature c) Focus d) Focal length e) Principal axis a) Pole:- The midpoint (Geometrical centre) of the mirror is called pole (P) of the mirror. b) Centre of curvature:- All normals of concave mirror will converge towards a point. This point is called centre of curvature(C) of the mirror. c) Focus:- All the reflected ray of concave mirror is intersecting at one point on the principle axis is called focus or focal point (F). e) Focal length:- The distance between pole and focal point of a mirror is called focal length (f). f) Principal axis - The horizontal line which passes through the centre of curvature and pole is called central axis or principal axis of the mirror. 9. What is Fermat’s principle ? Light select the path which takes the least time travel. It is also applicable to reflection of light. 10. The magnification of a plane mirror is +1. What is it mean? The magnification of a plane mirror is +1 means the size of the object is equeal to size of the image. 11. Why it is too difficult to shoot a fish swimming in the water? 1. It is very difficult to shoot a fish swimming in water. 2.Because its position appears to be shifted up from its original position due to reflection. 12. What are the factors that influence refractive index? 1. Nature of material 2. Wave length of light 13. Define the word lens? Lens :- A lens is madeup of a transparent material, which has atleast two curved surfaces. 14. Write the lens makers formula and explain the terms in it? Lens makers formula is = (n-1) [ - ] Here f = Focal length R1 and R2 are radii of curvature. n = Refractive index. 1
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------15. Write the mirror formula and explain the term? Mirror formula, = + . Here f = focal length u = object distance v = image distance. 16. Write the lens formula and explain the terms in it? Lens formula:- = Where, f = the focal length of the lens. u = object distance. v = image distance. 17. Write the formula for formation of image by curved surfaces? Image formula:- - = Where, n1 = refractive index of the first medium. n2 = refractive index of the second medium. u = image distance. v= Object distance. R = Radius of curvature. 18. Why do we call a concave mirror as a convergent mirror? 1. When parallel rays falls on the surface of a concave mirror, all the rays after reflection converses at one point on the principle axis toward a focus. 2. So, concave mirror is also called a convergent mirror. 19. Write the names of different types of lenses. Draw their diagrams?
20. Can a virtual image be photographed by a camera? Yes, a virtual image can be photographed by a camera. 21. Suppose you are inside the water in a swimming part near an edge. A friend standing on the edge. Do you find your friend taller or shorter than his usual height? Why? My friend appears to be taller. Reason:- 1. The light rays of my friend travelling from rarer to denser medium. 2. These rays bends towards normal line so apparent image of my friend which appears to be taller due to refraction. 22. A man wants to get a picture of a zebra. He photographed a white donkey after fitting a glass, with black stripes, on to the lens of his camera. What photo will he get? Explain? 1. Photographer will get a picture of white donkey only. 2. Because every part of lens forms an image so if we cover lens with, stripes still it forms a complete image. 23. Define power of a lens? Write its units? Power of a lens:- 1. The reciprocal of focal length is called power of lens. 2. Power of a lens, P = ( ) = ( ) 3. The unit of power is dioptre(D). 24. Define Presbyopia? How do we correct this defect? Presbyopia :- Presbyopia is vision defect when the ability of accommodation of the eye usually decreases with ageing. Correction :- Bi-focla lens is used to correct this type of eye defect. 25. What is the value of 1KWH in Joules? 1KWH = 36 x 105 Joules. 2
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------26. What is scattering of light? Scattering of light:- Atoms or molecules which are exposed to light absorb light energy and emit some part of the light energy in different directions is called scattering of light. 27. Define electric current? Electric current:- Electric current is defined as the amount of charge crossing any cross section of the conductor in one second. I= SI unit:- ampere(A). 28. Define ohm? Ohm :- If 1 Ampere of electric current passes between two points of potential differences 1 volt, then the resistance between them said to be 1 Ohm. 1 Ohm =
29. Why does a bird not get the shock when it stands on a ahigh voltage wire? 1. When the bird stands on a high voltage wire, there is no potential difference between the legs of the bird because it stands on a single wire. 2. So no current passes through the bird. Hence, it doesn’t feel any electric shock. 30. Define Ohm’s Law? Ohm’s Law:- At constant temperature, the potential difference of a conductor is directly proportional to current passing through it. V=IR 31. Are head lights of a vehicle connected in series or parallel? Why? (OR) Why don’t we use series arrangement of electrical appliances like bulb, television fan and other in our domestic circuits? 1. In a series combination if one of appliances is damaged, all the appliances are stopped working. 2. Hence we don‟t connect them in series. 32. Why does the picture appear distorted when a bar magnet is brought close to the screen of a television? Explain? 1. When a bar magnet is brought close to the screen of a television the picture appear destroyed. 2. This is due to the fact that magnetic field exerts a force on the moving charge. 33. State the Lenz’s law? Lenz’s law :- Lenz’s law states that “the induced current will appear in such a direction that it opposes the changes in the flux in the coil.” 34. Which of the various methods of current generation protects the nature well? Give examples to support your answer? 1. Tidal energy. 2. Hydro electric energy. 3. Wind energy. 4. Solar energy.
2 MARKS QUESTIONS 1. Why do we get dew on the surface of a cold soft drink bottle kept in open air? 1. When a cold soft drink bottle kept in open air, the water vapour in air condences. 2. So, water droplets are formed on the surface of the bottle. 2. If you are chilly outside the shower stall, why do you feel warm after the bath if you stay in bathroom? 1. In the bathroom, the number of vapor molecules per unit volume is greater than number of vapor molecules per unit volume outside the room. 2. When you try to dry yourself with a towel, the vapor molecules surrounding you condense on your skin and this condensation makes you feel warm. 3. What role does specific heat capacity play in a watermelon to keep it cool for long time after removing it from a fridge on a hot day? 1.Water melon contains large percentage of water. 2.Water has higher specific heat value. 3. Hence watermelon takes lot of time for cooling when compared to other fruits in a fridge. 3
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------4. Why do we sweat while doing work? 1. When we do work the water in the sweat glands starts evaporating. 2. This evaporation cools the body. 5. Write the differences between evaporation and boiling? Evaporation 1. The process of escaping of molecules from the surface of a liquid at any temperature is called evaporation. 2. Evaporation takes place at any temperature. 3. It is a cooling process. 4. Temperature of the system falls during evaporation.
Boiling 1. The process in which the liquid phase changes to gaseous phase at a constant temperature is called boiling. 2. Boiling takes place at constant temperature. 2. It is a heating process. 4. Temperature of the system remains constant during this process.
6. What would be the final temperature of a mixture of 50g of water at 200C temperature and50g of water at 400C temperature? Solution: -
T1= 200C T2 = 400C
Given m1 = 50g m2 = 50 g
Final temperature, T= ? Formula :-
T =
= =
=
!
= 300C ∴ The final temperature of a mixture is 300C. 7. By observing steel vessels and different images in them; Surya, a third class student asked some questions his elder sister Vidya. What may be those questions? 1. Why the image is not cleared visible? 2. Why the image is blurred? 3. Why the image is not as clear as in mirror? 4. Why the image sometimes enlarged? 8. Write the rules for sign convention? Rules mentioned for sign convention: - 1. All distances should be measured from the pole. 2. The distances measured in the direction of incident light, to be taken as positive. 3. The distances measured in the opposite direction of incident light, to be taken as negative. 9. Why do we prefer a convex mirror as a rear-view mirror in the vehicles? 1. Convex mirror always forms an erect and virtual image of the behind vehicle in the small mirror. 2. So, we prefer a convex mirror as a rear-view mirror in the vehicles. 10. How do you appreciate the use of reflection of light by concave mirror in making of TV antenna dishes? 1. In a concave mirror all reflected rays intersected at focal point. 2. The concave shape of a dish antenna helps to reflect the signal to the focal point of the dish. 3. A device known as feed horn is mounted at the focal point which gathers the signals and sends to a processing unit. 4. So, I appreciate the working process of T.V. antenna dishes. 11. State the laws of reflection of light? Laws of Reflection of Light: - 1. The angle of incidence is equal to the angle of reflection. 2. The incident ray, reflected ray and normal are lies in a same surface. 12. Why do stars appear twinkling? Stars appear twinkling due to multiple refraction at different layers of air of different densities, the light undergoes all the way to reach our eye. 13. What is meant bya refraction? Give some examples of daily life observations of refraction and explain? Refraction of light:- The process of changing speed at an interface when light travels from one medium to another medium, resulting in changes in direction is called refraction of light. 4
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------Examples:- 1. A coin kept at the bottom of a vessel filled with water appears to be raised. 2. A lemon kept in a glass of water appears to be bigger than its size. 3. When a thick glass slab is placed over some printed letters, the letters appear raised when viewed through the glass slab. Explanation:- When light ray travels from denser(water) to rarer(air), it diverges from normal and the lemon in water appear to be bigger in size. 14. Why does a diamond shine more than a glass piece cut to the same shape? 1. Diamond exhibits the property of total internal reflection due to its high refractive index and low critical 2. So, diamond shine more than a glass piece cut to the same shape. angle. 15. Collect the information about lenses used by Galileo in his telescope? Galileo Telescope :- 1. Galileo telescope consists of two lenses. 2. Convex lens of large focal length. It is called objective lens. 3.Concave lens of short focal length. It is called eye piece. 4. The eye piece forms the final and magnifying image. 16. Explain the formation of Mirages?
Formation of Mirages:-1. During the hot summer day, air just above the road surface is very hot and the air at higher altitudes is cool. 2. Light travels faster through the thinner hot air than through, the denser cool air above it. 3. When light falls from tall object such as tree from the sky passes through just above the road. 4. Due to the refraction of light, we fell the illusion of water being present on road. 5. This is called a mirage. 17. Distinguish between Convex lens and concave lens? Convex lens 1. Convexlens is thick at middle and thin at edges. 2. The shape of a convex lens is,
Concave lens 1. Concave lens is thin at middle and thick at edges. 2. The shape of a concave lens is,
3. It is also known as converging lens.
3. It is also known as diverging lens.
4. This lens is used to treat hypermetropia.
4. This lens is used to treat myopia.
18. A convex lens is made up of three different materials as shown in the figure. How many of images does it forms? 1. The given convex is made up of three different materials. 2. It forms three images as shown in the figure.
19. Expalin briefly the reason for the blue of the sky? 1. The reason for the appearance of sky in blue colour is due to the phenomenon of scattering of sunlight by the atoms or molecules present in the sky. 2. Our atmosphere contains Nitrogen(N2) and Oxygen(O2). 3. These molecule act as scattering centers for scattering of Blue light. 4. So the sky appears to be Blue in colour. 20. Name the phenomenon when white light is incident on a prism and write the names of the colours? 1. This phenomenon is called dispersion of light. 2. The formation of the clours are violet, indigo, blue, green, yellow, orange and red(VIBGYOR). 5
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. ---------------
21. If a white sheet of paper is stained with oil, the paper turns transparent. Why? 1. The refractive index of oil and refractive index of paper is same. 2. So, light passes from oil to paper become transparent. 22. A person is viewing distant object. If a converging lens is placed in front of his eye. Will he feel that the size of object has increased? Why? 1. Yes, if a converging lens is placed in front of his eye he will tell that the size of object has increased. 2. Because converging lens is a magnifying lens. 23. Why sun appears white in noon and red at sun set or sunrise? 1. During sunrise and sunset, except red light all colours scatter more and vanish before they reach you. 2. As a result sun appears red in colour during sunrise and sunset. 3. During noon hours, all colours reach your eye without much scattering. 4. Hence the sun appears white during noon hours. 24. How do you appreciate the nature of cilliary muscles in eye? 1. Ciliary muscle is helpful to change its focal length by changing radii of curvature of eye lens. 2. This process of adjusting focal length is called “accommodation”. 3. Due to this accommodation we see closer and distinct objects clearly. 4. So, we appreciate the working of Ciliary muscles in the eye. 25. Explain over loading of household circuits? How do you prevent it? 1. The maximum current that we can draw from the mains exceeds 20A, it may cause a fire. 2. This is called over loading. 3. The safety device fuse is used to prevent the overloading of electric current. 26. What are ohmic and non-ohmic conductors? Give some examples for them? 1. The material which obey Ohm’s law are called ohmic conductors. Ex:- All metals. 2. The material which do not obey Ohm’s law are called non-ohmic conductors. Ex:- LEDs are non ohmic materials. 27. What do you mean by electric shock? Explain how it takes place? (OR) What happens to our body if we touches a current wire of 240V? 1. The current passing through our body when we touch a live wire of 240V is given by, = 0.0024A. I= 2. Due to this functioning of organs inside our body get disturbed. 3. This disturbance inside our body is felt as electric shock. 28. Define Kirchhoff‟s Law? 1. The Junction law:- At any function point in a circuit where the current can devide, the sum of the currents into the junction must equal the sum of the currents leaving the junction. 2. The Loop law:- The algebraic sum of increments and decrements in potential differences across various components of a closed circuit loop must be zero. 29. What are the factors one which the resistance of conductor depends? Give the corresponds the # relation? (OR) Derive R = ρ$ . 1. The resistance of a conductor is directly proportional to the length of the conductor. i.e., R∝l …… (1) 2. The resistance of a conductor is inversely proportional to the area of a cross section of the conductor. i.e., R ∝ …… (2) 3. From (1) and (2), we get R ∝ ⟹ R = ρ , Where ‘ρ’ is a constant called specific resistance.
6
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------30. Give a few applications of Faraday’s law of induction in daily life? 1. Gadgets and scanners used for security check work on the principle of electromagnetic induction. 2. Transformers, electrical generators work on the principle of electromagnetic induction. 3. ATM cards, swiping machines are also the applications of Faraday’s law of electromagnetic induction. 4. Induction stove works on the principle of electromagnetic induction. 31. A bar magnet with North Pole facing towards coil moves as shown in fig. What happens to magnetic flux passing through the coil? If a bar magnet with north pole facing towards the coil then the magnetic flux passing through a coil then current is generated in the coil. 5. Take a bright metal ball and make it black with soot in a candle flame immerses it in water. How does it appear and why? (Make hypothesis and do the above experiment)
1. If a metal ball coated with soot of candle flame is immersed in water, then it appears shining. 2. Soot is non-stick to water. A thin air film is formed in between water and soot as shown in the figure. 3. The light ray is travelling from water(denser medium) to air(Rarer medium). 4. The angle of incidence is greater than the critical angle, total internal reflection takes place. 5. As the ray reflects at water air interface, the metal ball appears shining. 6. It is similar to shining of air bubble in water. 6. Take a bright glass vessel and pour some glycerine into it and then pour water up to the brim. Take a Quartz glass rod. Keep it in the vessel. Observe glass rod from the sides of the glass vessel. What change of you notice? What could be the reasons for these changes?
1.When this arrangement is viewed from side, the size of the glass rod appears increased in water and glass rod disappeared in glycerine. Reason:2. As shown in the figure, the vessel contains glycerine (n = 1.47) and water (n = 1.33) when glass rod immersed into the liquid the part in the glycerine disappears. 3. This is due to the fact that both glass rod (n = 1.5) and glycerine (1.47) have same refractive index. 4. When refractive Indies are same the speed of light is same in both media. 5. So no bending is takes place and hence no refraction takes place. 6. The part of the glass rod in water appears as larger than the original size of the rod. This is due to refraction. 5. What is the angle of deviation produced by a glass slab? Explain with ray diagram (AS7)? (TQ)
Angle of Deviation:- 1. The angle between incident ray and emergent ray is known as angle of deviation. 2. The angle of deviation produced by a glass slab is 00. 3. Because the incident ray and emergent rays are parallel to each other. 7
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------IMPORTANT PROBLEMS 1. An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm find the position and nature of image? Given:Radius of curvature R = 3m ! Focal length f = = = 1.5 m Object distance (u) = - 5m Image distance (v) =? ! ! Formula:- = + ⇒ = - = . - = + = = . ⇒v=
!
= 1.15 cm
∴ Virtual, erect and diminished image is formed at a distance of 1.15cm behind the mirror. 2. The absolute refractive index of water is 4/3. What is the critical angle of it? (AS1) (Ans: 48.50)(TQ) Given :The absolute refractive index of water = 4/3 !
(
= ! ⟹ Sin C = ⟹ Sin C = 0.75 ⟹ Sin C = sin 48.5o ⟹ C= 48.50 ∴ The critical angle of water is 48.50.
3. Determine the refractive index of benzene if the critical angle of it is 420. (AS1) (Ans: 1.51)(TQ) Given:The critical angle of Benzene = 420. Refractive index of Benzene, = )
=)
=
*
.++,
= ++, =1.51 ∴ The refractive index of a benzene is 1.51. -
4. Refractive index of glass relative to water is .. What is the refractive index of water relative to glass? (AS1) (TQ) , ) 0 12 34 Given:Refractive index of glass relative to water is =/ = ) 0 12 4 )
0 12 4
Refractive index of water relative to glass = )
0 12 34
/
= ,.
5. The focal length of a converging lens is 20cm. An object is 60cm from the lens. Where will the image be formed and what kind of image is it?
Given: -
Formula:-
Focal length, f = 20 Cm Object distance, u = - 60 Cm Image distance, v =? = -
⟹ = +
⟹ =
(In front of lens take ‘u’ as – ve sign)
+
⟹ =
+
-
+
⟹ =
! +
⟹
=
+
⟹ v = 30 cm ∴ Hence image is real, inverted and formed other side of the lens. 6. Doctor advised to use 2D lens. What is its focal length? Given:Power of the lens P = 2D. Formula:-
P=
(5 )
⇒f=
⇒ f=
= 50cm.
∴ The focal length of the lens is 50cm.
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------4 MARKS QUESTIONS 1. Explain the procedure of finding specific heat of solid experimentally? (OR) Sunnyleon wants to place a lid of more specific heat on a cooking vessel. For that she wants to know the specific heat of aluminium and copper. What are the appratus she required ? How would she conducts this experiment? Aim:- To find the specific heat of given solid. Apparatus:- Calorimeter, thermometer, stirrer, water, steam heater, wooden box and lead shots. Procedure:- 1. Let the mass of the calorimeter along with stirrer is ‘ m1’ gm. 2. Mass of the calorimeter and water is ‘ m2’ gm. 3. The temperature of the calorimeter is noted (T10C ). 4. The heated Lead pieces (m3 gm and T20C) are quickly transferred in to calorimeter, with minimum loss of heat. 5. Now the resultant temperature is noted as T30C. 6. By using the formula we calculate the specific heat of the given solid, Sl =
)6 ( ( 8
) )7 ( 8 8)
)
) (
2. How do you appreciate the role of higher specific capacity value of water in stabilizing atmospheric temperature during winter and summer seasons? 1. The sun delivers a large amount of energy to the earth daily. 2. The oceans, absorb this energy for maintaining a relatively constant temperature. 3. The oceans behave like heat “store houses” for the earth. 4. So, I appreciate the role higher specific capacity value of water in stabilizing atmospheric temperature during winter and summer seasons. 9:; :
3. How do you verify experimentally that 9:; < is constant? (OR) Derive the formula of relation between angle of incident and angle of refraction of a prism? ) Aim: -To verify that is a constant. ) Materials required:-A plank, white chart, protractor, scale, small black painted plank, a semi circular glass disc of thickness nearly 2cm pencil and laser light.
Procedure:-1. Make a chart as shown in the figure. 2. Place a semi-circle glass disc so that its diameter coincides with the line “MM” 3.Send a laser light along a line which makes 150 with “NN”. 4. Measure its corresponding angle of refraction by observing light coming from outside of the glass slab. 5. Repeat this experiment with various values of angle of incidence, refraction and noted below. S.No
i
r
Sin i
)
6. From the above table we observe that )
Sin r
Sini Sinr
is a constant.
4. Explain the formation of Rainbow? (OR) After rainfall Sreekar looking towards the sky and observed the formation of rainbow. How you are explain the formation of rainbow with the basis of dispersion of light to Sreekar? Formation of Rainbow: - 1. The beautiful colours of rainbow are due to dispersion of the sunlight by millions of tiny water droplets. 2. Let us consider a case of an individual water drop. 3. The ray of sunlight enters the drop near its top surface. 9
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------4. At this first refraction, the white light is dispersed into its spectrum of colours, violet being deviated the most and red the least. 5. If you see at an angle between 400 and 420, you will observe remaining colours of VIBGYOR.
5. Collect the information on working of optical fibres. Prepare a report about various uses of optical gibes our daily life? (OR) While doing heart operation Osama Bin Laden observed that a thin pipe is passed to observe internal parts on a computer screen. He come to know that it was an optical fibre. How does the optical fibre works?
Working:- 1. In a optical fibre total internal reflection takes place as shown in the figure. 2. The light is thus transmitted along the fibre. Uses:- 1. Optical fibre are used in endoscopy to see the internal organs of out body. 2. Optical fibres are used in transmitting communication signals through light pipe. 3. Optical fibres are used in international telephone cables and large computer network etc. 6. How do you correct the eye defect, Myopia? (OR) Prabhas, a tenth class boy sitting last bench of the class room. He was unable to see the letters on the black board clearly.Which type of eye defect he suffered? How would you correct it? Myopia: 1. The defect in which people cannot see objects beyond far point is called Myopia. 2. Myopia is also known as ‘near sightednesses’.
Correction: - Biconcave lens is used to correct the eye defect Myopia.
7. Explain the correction of the eye defect, Hypermetropia? (OR) Surya wear a spectuicals and his friend Sreekar observed that Surya eyes are appeared bigger through the specticals. Which type of eye defect it is? How would you correct it? Hypermetropia:-1.The defect in which people cannot see objects before near point is called Hypermetropia. 2. Hypermetropia is also known as ‘farsighted nesses.
Correction: - Biconvex lens is used to correct the eye defect Hypermetropia.
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------12. How do you find experimentally the refractive index of material of the prism? Aim:- To find the refractive index of the prism. Material required:- Prism, Piece of white chart, pencil, pens, scale and protractor. Procedure: -
1. Take a prism and place it on the white chart and draw the boundary lines by using a pencil. 2. Remove the prism and name the vertices as P, Q and R. 3. Calculate the angle of the prism (A=600) and noted in your book. 4. Draw a normal to PQ at M and draw a line with 300 to the normal. 5. This is incident ray AB. Fix two ball pins on this ray at A and B. 5. Place the prism in its exact position and fix another two pins at C and D such that all four pins appear to lie along the same line by seeing the images of pins through the prism from the other side PR. 6. Draw line joining C and D and extend it to meet PR at N this is emerging ray. 7. Draw normal at PR at N and measure the angle between normal at N and emergent ray. 8. If we extent the incident ray AB and emergent ray CD, they meet at O. 9. Measure angle between these two rays and note as angle of deviation (d). 10. The same experiment repeated for different angles of incidence and measure corresponding angle of deviation and noted down in the following table. S.No Angle of incidence (i1) Angle of emergence (i2) Angle of deviation (d) 1 300 2 400 3 500 4 600 5 700 11. We draw a graph by taking angles of incident on X-axis and angles of deviation (d) on y-axis. 12. The graph is a curved line as shown in the figure. Find angle of minimum deviation (D).
13. Now we can calculate the refractive index of the material of the prism by using the formula, ABC
n=
) (
)
A
) ( )
8. Deduce the expression for the equivalent resistance of the three resistors connected in series?
1. Connections are made as shown in the figure. 2. From Ohm’s law at V1 = I R1, V2 = I R2 and V3 = I R3 3. Since the resistors are connected in series, V = V1 + V2 + V3 11
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------4. Substituting the values of voltages in the above equation I R = I R1 + I R2 + I R3 I R = I (R1 + R2 + R3) 5. Thus, R = R1 + R2 + R3 9. Deduce the expression for the equivalent resistance of the three resistors connected in parallels?
1. Connections are made as shown in the figure. 2. Ohm’s law as, I1= , , I2 = and I3 = ! . 3. Since the resistors are in parallel, I = I1 + I2 + I3 4. Substituting the value of currents in the above equation,
=
+
V ( ) =V ( 5. Thus, =
+
+ ⟹R= !
+ +
!
+
! !
!
)
!
10. State Ohm’s law. Suggest an experiment to verify it and explain the procedure? (OR) Suggest an experiment to show the ratio of potential difference and current is constant. How can you conduct it? Ohm’s law: -Ohm’s law states that the potential difference between the ends of a conductor is directly proportional to the electrical current passing through it. Aim: - To verify Ohm’s law. Material Required: - Battery, Rheostat, Resistance, Ammeter, Voltmeter and wire.
Procedure: -1. Connections are made as shown in the figure. 2. By changing the position of the rheostat, change the flow of current in the circuit. 3. Note the reading in the voltmeter and ammeter and tabulated below. E S.No Voltmeter Reading(V) Ammeter Reading R= : (i) 1. 2. 3. 4. 4. From the above table we observe that = constant. This is equeal to resistance of the wire. 5. So, Ohm’s law is verified. 11. A house has 3 tube lights, two fans and a Television. Each tube light draws 40W. The fan draws 80W and the Television draw 60W. On the average, if all the tube lights are kept on for five hours, two fans for 12 hours and the television for five hours every day. Find the cost of electric energy used in 30 days at the rate of Rs. 3.00 per KWH ? Energy consumed by 3 tube lights in a day E1= p × t = 3×40W×5h = 600 Wh. Energy consumed by 2 fans in a day E2= p × t = 2× 80W ×12h = 1920 Wh. Energy consumed by television in a day E3= p × t = 60W × 5h = 300 Wh. Total energy consumed in a day = 600 + 1920 + 300 = 2820 Wh. Total energy per month = 2820 Wh × 30 = 84600 Wh = 84.6 KWh. Cost of 1 unit charge = Rs. 3.00/∴ Cost of 84.6 Watts = 84.6 x 3 = Rs. 253.8/12
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------12. Derive Faraday’s law of induction from conservation of energy? (OR) How do you appreciate Faraday’s law, which is the consequence of conservation of energy?
1. Connections are made as shown in the figure. 2. the force applied by the cross wire is given by, F = BIl -------(1) 3. The work done by us in moving the cross wire convert into electrical energy. 4. So, Work, W = Fs=BIls-------(2) ⇒ W = (Bls)I = (∆Φ) I ( since ∆Φ= Bls) 5. Deviding both sides of this equation with ∆t. F ∆Φ We get ∆ = ( Φ )I ∆Φ
⇒ Power, p = εI (Since induced emf, ε = Φ ) 6. Thus the electrical power generated in the circuit is equeal to product of induced emf and current. 7. This is nothing but conservation of energy. 13. Explain the working of electric motor with a neat diagram?
Working: 1. An electric motor consists of a rectangular coil ABCD called armature and kept in between the parements magnets as shown in the figure. 2. When current is passing through the coil armature gets half rotation. 3. But the Coil continuous the rotation because of rotational inertia of motion. 4. In the same way couple rotates the coil in the same direction. 5. It is the working of an electrical motor. 14. Explain the working of AC electric generator with a neat diagram?
Working of an Ac elector generator:1. Consider the rectangular coil is held between the poles of curve-shaped permanent magnet as shown in the figure. 2. As the coil rotates, the magnetic flux passing through coil changes and an induced current is generated in the coil. 3. The current obtained by this process changes its direction alternatively. 4. This current is called alternating current (AC). 13
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------15. Explain the working of DC generator with a neat diagram?
Working of a DC generator:1. Consider the rectangular coil is held between the poles of curve-shaped permanent magnet as shown in the figure. 2. As the coil rotates, the magnetic flux passing through coil changes and an induced current is generated in the coil. 3. The current obtained by this process cannot change its direction. 4. This current is called Direct current (DC).
Practice the following Diagrams 1. Draw the ray diagrams of reflection of light by concave mirror in the following cases? a). When an object is placed on the principle axis of a concave mirror away from the centre of curvature? (Page-59, Fig-24) b). When an object is placed on the principle axis of a concave mirror between the mirror (pole) and focal point? (Page-59, Fig-25) c). When an object is placed on the principle axis of a concave mirror between focal point and centre of curvature? d). When an object is placed on the principle axis of a concave mirror on focal point? (Page-60,Fig-26) e). When an object is placed on the principle axis of a concave mirror on centre of curvature? (Page-60, Fig-27) 2. Draw the ray diagrams for image formation by convex lens in the following cases? a). When the object is placed beyond the centre of curvature? (Page-123, Fig-13) b). When the object on the centre of curvature? (Page-123, Fig-14) c). When the object is placed between the centre of curvature&focal point?(Page-123,Fig-15) d). When the object is placed on focal point? (Page-123, Fig-16) e). When the object is placed between focal point and optic centre? (Page-124, Fig-17) f). When the object is placed at infinity distance from centre of curvature? (Page-120, Fog-8{a}) 3. Draw the diagram of magnetic field lines when current passes through the solenoid and labeled the parts? (page-266, Fig-6{b})
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------CHEMISTRY IMPORTANT QUESTIONS-2017 1 MARKS QUESTIONS 1. Why do we apply paint on iron articles? We apply paint on iron articles to shield their surfaces from oxygen and moisture to prevent the corrosion. 2. Which gas is usually liberated when an acid reacts with a metal? Hydrogen (H2) gas. 3. What is the use of keeping food in air tight containers? 1. Keeping food in air tight containers helps to slow down oxidation process. 2. So that we can avoid spoiling of food. 4. What is baking powder? How does it make the cake soft and spongy? Baking powder: 1. Baking powder is a mixture of baking soda and tartaric acid. 2. Carbon dioxide produced during the reaction causes bread or cake to rise making them soft and spongy. NaHCO3 + H+ → Na+ + CO2 + H2O 5. Give two important uses of washing soda and baking soda? Uses of washing soda: 1. It is used in glass and soap and paper industries. 2. It is also used for removing permanent hardness of water. 1. Baking soda is an ingredient in antacids. Uses of baking soda: 2. It is also used in fire extinguishers and acts as mild antiseptic. 6. While diluting an acid, why is it recommended that the acid should be added to water and not water to the acid? 1. If water is added to a concentrated acid, the heat generated may cause the mixture to splash out and cause burns. 2. The glass container may also break due to excessive local heating. 7. Write any two uses of Bleaching powder? Uses of Bleaching Powder:1. It is used in the textile industry for bleaching washed clothes in laundry. 2. Used as an oxidizing agent in many chemical industries. 3. Used for disinfecting drinking water to make it free of germs. 4. Used as a reagent in the preparation of chloroform. 8. What happens when an acid or base is mixed with water? 1. When an acid or base is mixed with water its concentration is decreases means diluted. 2. In this process heat is liberated. 9. Why pure acetic acid does not turn blue Litmus to Red? Pure acetic acid not containing the H+ ions. So, it does not turn blue litmus to red. 10. Define PH ? PH :- The negative logarithm of H+ ions concentration is called pH. It was introduced by Sorenson. 11. What will happen if the pH value in our body increases? The pH value of our body increases it should be raise the digestive problems. 12. Is the substance present in antacid tablet acidic or basis? The substance present in the antacid is mild base. 13. What is the value of Plank’s constant? h = 6.626 X 10-34 Js (or) 6.626 X 10-27 erg.s 14. What is electromagnetic spectrum? Electromagnetic spectrum :- 1. Electromagnetic waves can have a wide variety of wavelengths. 2. The entire range of wavelengths is known as the electromagnetic spectrum. 15. Which rule is violated in the electronic configuration of 1s0 2s2 2p4 ? Hund’s rule. 15
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------16. What are degenerate orbital’s? Orbital which have same energy are called degenerate orbital’s 17. How many ml values are possible for l = 3? The possible ml values for l = 3 are 7 they are -3, -2, -1, 0, +1, +2, +3. 18. Write the electronic configuration of ‘Cr’ and ‘Cu’? Cr = 24 1s2 2s2 2p6 3s2 3p6 4s1 3d5 (or) [Ar] 4s1 3d5 Cu = 29 1s2 2s2 2p6 3s2 3p6 4s1 3d10 (or) [Ar] 4s1 3d10 19. What is meant by Dobernier triad and give one example? 1. Dobernier arranged the elements in ascending order of their atomic weights. 2. the atomic weight of the middle element is the average of the atomic weights of the first and third elements. 3. This statement is called the Dobereiner’s law of triads. Ex:- Li. Na, K 20. Comment on the position of hydrogen in periodic table ? 1. The element Hydrogen belongs to IA group of the periodic table. 2. Hydrogen electronic configuration is 1S1. 3. So, no fixed position to be given to hydrogen in the periodic table. 21. Represent each of the following atoms using Lewis notation: a. Beryllium b. Calcium c. Lithium Be
Ca
Li
22. Represent the molecule H2O using Lewis notation? One atom of oxygen shares its two electrons with two hydrogen atoms to form a water molecule.
23. What is meant by a Metallurgy? Metallurgy :- “Metallurgy is the process of extraction of metals from their ores”. 24. Give any two examples of ores with their formulas? Ore Formula Bauxite Al2O3 2H2O Cinnabar HgS 25. Define the terms 1. Gangue 2. Slag. Gangue:- The impurity present in the ore is called Gangue. Slag:- Slag is a feasible material which combines the flux and impurities. 26. Give the name functional group (i) –CHO (ii) –C=O. i. –CHO is Aldehyde. Ii. –C=O is Ketone. 27. Define allotropy? Give an example? Allotropy :- The occurrence of same element in two or more different forms is known as allotropy. Ex :- Diamond and Graphite. 28. What is Vinegar? Give its uses? 5 – 8% solution of acetic acid in water is called Vinegar. It is used to preserve pickle for long time. Acetic acid is present in the vinegar. 29. What is a catenation? Catenation :- Catenation is the phenomenon in which atoms of same element join together to form a long chain. 30. What is micille? Micille :- A spherical aggregate of soap molecules in water is called “Micelle”
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------2 MARKS QUESTIONS 1. Why does respiration considered as an exothermic reaction? 1. The starch present in our food breaks down to form glucose. 2. This glucose combines with oxygen in the cells of our body and releases energy. 3. So it is considered as an exothermic reaction. 4. C6H12O6 + 6O2 → 6CO2 + 6H2O +Q (Energy) 2. What do you meant by corrosion? How can you prevent it? 1. When some metals are exposed to moisture, acids, etc., they tarnish due to the formation of respective metal oxide on their surface. This process is called corrosion. 2. Corrosion can be prevented by shielding the metal surface, painting, oiling, greasing, galvanizing, chrome plating or making alloys. 3. Explain rancidity?How can you prevent it? Rancidity: -1. Rancidity is an oxidation reaction. When fats and oils are oxidized they become rancid. Their smell and taste changes. 2. Oxidation reactions in food material that were left for a long period are responsible for spoiling of food. 3. Rancidity can be prevented by adding preservatives like vitamin C and vitamin E and also anti oxidants. 4. Write the differences between oxidation and reduction? Oxidation :- ‘Oxidation’ is a reaction that involves the addition of oxygen or removal of hydrogen. Reduction :- ‘Reduction’ is a reaction that involves the addition of hydrogen or removal of oxygen. 5. What are exothermic and endothermic reactions? Exothermic reactions :- In some chemical reactions heat energy is liberated is called exothermic reactions. Ex :- 1. C + O2 → CO2 + Q 2. Glucose is dissolved in water. 3. Ammonia is dissolved in water. 4. Sodium hydroxide is dissolved in water.
Endothermic reactions :- In some chemical reactions heat energy ig observed is called endothermic reactions. Ex:- 1. C(graphite) + 2H2 → CH4 - Q 2. Coal is burnt. 3. Burning of crackers. 4. Dilution of acids or bases. 6. What is a neutralization reaction? Give two examples? Neutralization reaction :- The reaction of an acid with a base to give a salt and water is known as neutralization reaction. Ex: Na OH + HCl → NaCl + H2O 7. What are antacids? Give an example? Antacids:- 1. Antacids are mild alkaloids. 2. These are used for getting relief from acidity and indigestion of stomach. 3. Ex: - Milk of Magnesia[Mg(OH)2] is an antacid. 8. Why does tooth decay start when the pH of mouth is lower than 5.5? 1. Bacteria present in the mouth produce acids by the degradation of sugars and food particle remaining in the mouth. 2. Due to the formation of acids, the pH of the mouth is shifted to acidic. 3. Hence, tooth decay starts when the pH of the mouth is lower than 5.5. 9. Plaster of Paris should be stored in moisture – proof container. Explain why? 1. Plaster of Paris is a white powder and on mixing with water, it sets into hard solid mass due to the formation of Gypsum. 2. So, it should be stored in moisture – proof container. 10. Fresh milk has a pH of 6. How does the pH change as it turns to curd.Explain your answer? 1. When milk is turns to curd the lactobacillus keeps growing and it breaking down the lactose in to lactic acid which acidified the milk even further. 2. So, the pH value of the curd is changed. 17
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------11. Which What are olfactory indicators? Give an example? Olfactory indicators :- Olfactory indicators are substances which have different odor in acid and base solutions. Ex:- Onion and Vanilla essence. 12. i. An electron in an atom has the following set of four quantum numbers to which orbital it belongs to: ii. Write the four quantum numbers for 1SI electron. n l ml ms H 2 0 0 +I 1. It belongs to 2s1. 2.
n 1
l ml ms 0 0 +
13. How many elliptical orbits are added by Somerfield in third Bohr’s orbit? What was the purpose of adding these elliptical orbits? Somerfield added two elliptical orbits to Bohr’s third orbit. Purpose:1. Bohr’s atomic model fails to explain atomic spectra. 2. So, Somerfield modified Bohr’s atomic model by adding elliptical orbits to explain the fine spectrum. 14. Rainbow is an example for continuous spectrum – explain? 1. Seven colours namely Violet, Indigo, Blue, Green, Yellow, Orange and Red (VIBGYOR) in a rainbow. 2. The colours in a rainbow spread continuously from one point to another. 3. Therefore rainbow is a continuous spectrum. 15. What information does the quantum numbers provide? The three quantum numbers n, l, and ml describe the size (energy), shape, and orientation, respectively, of an atomic orbital in space. 16. Using the periodic table, predict the formula of compound formed between and element ‘X’ of group 13 and another element Y of group 16. 1. The valence of 13th group element X is 3. 2. The valence of 16th group element Y is 2. 3. The formula of the compound is X2Y3. 17. An element X belongs to3rd period and group 2 of the periodic table. State (a) The no. of valence electrons (b) The valence (c) Whether it is metal or a non-metal? 1. The number of valence electrons is 2. 2. The valence of element is +2. 3. It is a metal. 18. Why does Sodium always form a cation where as Fluorine atom always forms an anion? When sodium (Na) atom loses one electron to get octet electron configuration it forms a cation (Na+) and gets electron configuration that of Neon (Ne) atom. + + e11Na → 11Na 19. Give the reason for low melting point for covalent compound when compared with ionic compounds? 1. The forces of attractions among ionic compounds are strong. 2. The forces of attractions among covalent molecules are weak. 3. Therefore, covalent compounds has low melting and boiling point compare than ionic compound. 20. What is octant rule? How do you appreciate role of the ‘octant rule’ in explaining the chemical properties of elements? Octant rule:- The atoms of the elements contain eight electrons in the valency shell is called octant rule. Role of octant in chemical properties of elements: 1. All the inert gases have octant configuration except helium. 2. So, they do not participate any chemical reactions. 3. If any group of elements try to get octant configuration by losing or sharing of electrons because of stability. 4. In this way, the octant rule helps in explaining the chemical properties of elements.
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------21. A chemical compound has the following Lewis notation: a. How many valence electrons does element Y have? Ans: 6 b. What is the valence of element Y? Ans: 2 c. What is the valence of element X? Ans: 1 d. How many covalent bonds are in the molecule? Ans: Two e. Suggest a name for the elements X and Y? Ans: ‘X’ is hydrogen and ‘Y’ is oxygen. The molecule formed here is H2O (Water). 22. What is thermite process? Mention its applications in daily life? Thermite process: Thermite process involves the chemical reaction of metal oxides with aluminum. 2Al + Fe2O3 → Al2O3 + 2Fe + Heat 2Al + Cr2O3 → Al2O3 + 2Cr + Heat Applications in daily life: 1. In this process the reaction of Iron oxide (Fe2O3) with Aliminium is used to join the railway tracks or cracked machine parts. 23. Write a note on ore dressing in metallurgy? 1. Dressing means simply getting rid of as much of the unwanted rocky material as possible before the ore is converted to the metal. 2. The methods of dressing or concentration of ore and gangue. a. Hand Picking b. Washing c. Froth flotation. d. Magnetic Separation. 24. Write short notes on each of the following: 1. Roasting 2. Calcination 3. Smelting. 1. Roasting: Roasting is a process of heating the ore strongly in a free supply of air or oxygen. Ex: 2ZnS(s) + 3O2(g) →2ZnO(s) + 2SO2(g) 2. Calcination: Calcination is a process of heating the ore strongly in the absence of air or oxygen. Ex: MgCO3(s) → MgO(s) + CO2(g) 3. Smelting: Roasting is a process of heating the ore strongly in a free supply of air or oxygen. Ex: The following reactions are takes place inside the furnace. 2C(s) + O2 → 2CO Fe2O3(s) + 3CO (g) →2Fe (l) + 3CO2(g) CaCO3(s) → CaO(s) + CO2 CaO(s) + SiO2(s) → CaSiO3(l) 25. Give an example for estarification reaction? Estarification reaction :- The reaction between carboxylic acid and alcohol in the presence of conc. H2SO4 to form a swept odoured substance, ester with functional group is called estarification. JK;L.MI9NO
CH3COOH + CH3CH2OH PQQQQQQR CH3COOH CH2 CH3 +H2O 26. What happens when a small piece of sodium is dropped into ethanol? (OR) Explain how sodium ethoxide is obtained from ethanol? Give chemical equations? When ethanol is react with sodium to liberate hydrogen and form sodium ethoxide. 2C2H5OH + 2Na → 2C2H5ONa + H2↑ 27. Define homologoes series of carbon compounds? Give examples? Homologoes series: The series of carbon compounds in which two successive compounds differ by – CH2 unit is called Homologous series. Ex: - Alkanes, Alkenes, Alkynes etc. When ethanol is react with sodium to liberate hydrogen and form sodium ethoxide. 2C2H5OH + 2Na → 2C2H5ONa + H2 28. How do you appreciate the role of esters in everyday life? 1. Esters having sweet or pleasant fruity smell. 2. Esters are used in the manufacturs of madicines and vitamins. 3. So, I appreciate the role of esters in everyday life. 29. Draw the Lewis dot structure of Methane molecule? 1. In the formation of methane(CH4) molecule, carbon contributes 4 electrons, (one electron to each hydrogen atom) and 4 hydrogen atoms contribute one electron each. 2. Thus in CH4 molecule, there are four C – H covalent bonds as shown below. 19
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. ---------------
30. Write the IUPAC names of the following compounds? a). C5H12 b). C7 H16 c) CH4 d)C2H2 a). Pentane b). Heptane c). Methane d). Ethyne
4 MARKS QUESTIONS 1. Write the types of chemical reactions with examples? 1. Chemical Combination:- A reaction in which single product is formed from two or more reactants is known as chemical combination reaction. Ex:- 2Mg(s) + O2 (g) → 2MgO (s) 2. Decompostion Reaction:- When a decomposition reaction is carried out by heating, it is called thermal decomposition reaction. S 4
Ex:- CaCO3 (s) TUUUV CaO(s) + CO2 (g) 3. Chemical displacement reaction:- In a displacement reaction one element replaces another element from its compound. Ex:- Zn + CuSO4→ZnSO4 + Cu 4. Chemical double displacement reaction:In a double displacement reaction the reactants exchange their constituents chemically and form two new compounds. Ex:BaCl2 + Na2SO4→BaSO4 + 2NaCl 2. Balance the following chemical equations. a) Zinc + Silver nitrate → Zinc nitrate + Silver. b) Aluminum + copper chloride → Aluminum chloride + Copper. c) Hydrogen + Chlorine. → Hydrogen chloride. d) Ammonium nitrate → Nitrogen + Carbon dioxide + water. Balanced chemical equations:a) Zinc + Silver nitrate → Zinc nitrate + Silver. Zn + 2AgNO3→ Zn (NO3)2 +2Ag b) Aluminum + copper chloride → Aluminum chloride + Copper. 2 Al + 3 Cu Cl2→2 Al Cl3+ 3Cu c) Hydrogen + Chlorine→ Hydrogen chloride. H2+ Cl2→ 2 HCl d) Ammonium nitrate → Nitrogen + Oxygen + water. 2NH4NO3→2N2 + O2 + 4H2O 3. A light yellow colour substance on a watch glass is planced in the sun light and change into gray colour. a). What is the light yellow substance? Ans :- Silver bromide (light yellow colour) b). What is the gray colour substance? Ans :- Silver metal. c). Which type of chemical reaction it is? Ans:- Photochemical reactions. )
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d). Write the chemical equation for the reaction? Ans :- 2AgBr(s) TUUUUUUUV 2 Ag (s) + Br2 (g) 4. How the displacement reaction is takes place in a calcium carbonate? (Or) Conduct an activity to show that heat energy is required for the decomposition of some chemical substances? 1. Take a pinch of calcium carbonate (lime stone) in a boiling tube. 2. Heat the boiling tube over the flame of spirit lamp or burner. 3. Now bring a burning match stick near the evolved gas as shown in the figure. 4. The burning match stick is put off. 5. On heating calcium carbonate decomposes to calcium oxide and carbon dioxide. S 4
CaCO3 (s) TUUUUUUUUUV CaO(s) + CO2 (g) 6. From this activity we can prove that heat energy is required for the decomposition of some compounds.
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. ---------------
5. Compounds such as alcohols and glucose contain hydrogen but are not categorized as acids.Describe an activity to prove it?
1. Prepare a solution of glucose and alcohol. 2. This solution is keeping in a beaker and arranges the two electrodes as shown in the figure. 3. We will notice that the bulb does not glow in both glucose and alcohol solutions. 4. This indicates that solutions of both glucose and alcohol do not have H+ ions which carry electricity through them. 5. Hence, the compounds of glucose and alcohol are not categorized as acids. 6. Define the terms? a). Strong acid b). Weak acid c). Strong base d). Weak base a). Strong acids:- An acid which is completely ionized in water and thus produces a large amount of hydrogen ions is called strong acid. HCl (aq) → H+ (aq) + Cl- (aq) b). Weak acids:- An acid which is partially ionized in water and thus produces a small amount of hydrogen ions is called a weak acid. CH3COOH(aq) → CH3COO- (aq) + H+ (aq) c). Strong base:- A base which completely ionizes in water and thus produces a large amount of hydroxide ions (oH-) is called strong base. NaoH (s) + water→ Na+ (aq) + OH- (aq) d). Weak base:- A base which is partially ionized in water and thus produces a small amount of hydroxide ions is called a weak base. Mg(OH)2 (s) +Water → Mg2+ (aq) + 2OH (aq) 7. What is meant by water crystallization of a substance ? Describe an activity to show the water of crystallization? Water of crystallization:- Water of crystallization is the fixed number of water molecules Chemically attaches to each formula unit of a salt in its crystalline form.
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------Activity :- 1. Take a few crystals of copper sulphate in a dry test tube and heat the test tube. 2. After heating the blue colour of the copper sulphate turns to white. 3. Add few drops of water to white coloured copper sulphate returns to blue colour. 4. When these crystals are heated, water present in crystals is evaporated and the salt turns white. 8. Explain the significance of three Quantum numbers in predicting the position ns of an electron in an atom? 1. The principle quantum number (n) gives the size and energy of the orbit. 2. The angular momentum quantum number (l ) gives the shape of the sub-shell. 3. The magnetic quantum number (m) gives the orientation of the orbital in the presence of magnetic field. 9. a. How many maximum number of electrons can be accommodated in a principal energy shell? b. How many maximum number of electrons can be accommodated in a sub shell? c. How many maximum number of electrons can be accommodated in an orbital? d. How many sub shells will be present in a principal energy shell? e. How many spin orientations are possible for an electron in an orbital? a. ‘2n2’, where n is the principle quantum number. b. 2(2l +1), where l = 0,1,2,3…. c. 2. d. The number of sub shells will be present in a principal energy shell is ‘n’ e. The spin orientation of the electron is clockwise (↑) and anticlockwise (↓) direction. They are H H represented by +I and -I . 10. In an atom the number of electrons in m shell is equeal to the number of electrons in the K and L shell. Answer the following questions? a. Which is the outer most shell? Ans :- N-Shell. b. How many electrons are there in its outermost shell? Ans :- 2 electrons . c. What is the atomic number of an element? Ans :- Atomic number is 22. d. Write the electronic configuration of the element? Ans :- 1S2 2S2 2P6 3S2 3P6 4S23d2. 11. Draw the shape of s, p and d orbital diagrams? (AS-5)
12. Define the modern periodic Law. Discuss the construction of the long form of the periodic table? Modern Periodic Law:The properties of the elements are the periodic functions of their atomic number. Long form of the periodic table: 1. The modern periodic table has 7 periods and 18 groups. 2. The first periodic has two elements. 3. Second and third period have 8 elements in each. 4. Fourth and fifth periods have 18 elements in each. 5. Fifth period has 18 elements. 6. Sixth period has 32 elements. It is the longest period. 7. Seventh period is incomplete. 8. Lanthanides and Actinides are placed at the bottom of the periodic table.
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------13. Explain how the elements are classified into s, p, d and f- block elements in the periodic table and give the advantage of this kind of classification? S- Block elements: 1. The valence electrons enter into s-orbital is called s- block elements. 2. The general electronic configuration of s-block elements is ns1 to ns2. P- Block elements: 1. The valence electron enter into p-orbital is called p-block elements. 2. The general electronic configuration of p-block elements is ns2 np1 to ns2 np6. d- Block elements: 1. The valence electron enter into d- orbital is called d-block elements. 2. The general electronic configuration of d-block elements is (n-1) d1-10 ns1 or 2 . f- Block elements: 1. Inner transition elements are called f- block elements. 2. The lanthanides and actinides are belongs to f-block elements. 14. What is a periodic property? How does the following change in a group and period? Explain? i. (a) Atomic radius (b) Iodization energy (c) Electron affinity (d) Electron negativity. S.No 1 2 3 4
Periodic property Atomic radius Iodization energy Electron affinity Electron negativity
Period Decreases Increases Increases Increases
Group Increases Decreases Decreases Decreases
15. What is ionization energy? What are the factors that effecting the ionization energy? Ionization energy :- Ionization energy is the minimum energy required to remove an electron from the outer most orbital of an gaseous state atom. Factors :1. Nuclear charge. 2. Screening effect or sheilding effect. 3. Penetration power of the orbitals. 4. Stable configuration. 5. Atomic radius. 16. What is hybridization? Explain the formation of the following molecules using hybridization. a). Be Cl2 b). BF3 Hybridization: Hybridization is the concept of mixing atomic orbitals into new hybrid orbital’s suitable for the pairing of electrons to form chemical bonds in valence bond theory. Formation of Be Cl2 : 1. The electronic configuration of ‘Be' is 1S2 2S2. 2. The electronic configuration of ‘Cl' is 1S2 2S2 2P6 3S2 3Px2 3Py2 3Pz1. 3. Now the 2Px1 orbital of ‘Be' atom reacts with 3Pz1 orbital of ‘Cl' and forms BeCl2 as shown below.
Formation of BF3 : 1. The electronic configuration of ‘B’ is 1S2 2S2 2Px1. 2. The electronic configuration of ‘F’ is 1S2 2S2 2P6 3S1 3. Now the three 3S1 orbital’s of the ‘B’ atom react with 2S1 2Px1 2Py1orbital of ‘F’ and forms BF3 as shown below.
17. Explain the formation of the following molecules using valence bond theory. a) Formation of N2 molecule. b) Formation of O2 molecule. a) Formation of N2 molecule:- 1. The electronic configuration of ‘N’ atom is 1S2 2S2 2P3. 2. Nitrogen has three unpaired electrons in the ‘P’ orbital. 3. When two nitrogen atoms approach each other, the bond is formed in between two nitrogen atoms by sharing of electrons. 4. Therefore, there is a triple bond between two nitrogen atoms in N2 molecule. 23
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b) Formation of O2 molecule:- 1. The electronic configuration of oxygen atom is 1S2 2S2 2P4. 2. Oxygen has two un paired electrons in the ‘P’ orbital. 3. When two oxygen atoms approach each other, the bond is formed in between two oxygen atoms by sharing of electrons. 4. Therefore, there is a double bond between two oxygen atoms in O2 molecule.
18. Write short notes on froth floatation process?
1. This method is mainly useful for sulphide ores. 2. The ore with impurities is finely powdered and kept in water taken in a floatation cell. 3. Air under pressure is blown to produce froth in water. 4. Froth is obtained, takes the ore particles to the surface where as impurities settle at the bottom. 5. Froth is separated and washed to get ore particles. 19. What is the activity series? How it helps in extraction of metals? Activity Series: 1. Arrangement of the metals in descending order of their reactivity is known as activity series. W,XY,JY,Z[,$# a;,b],cd,Je $[,Je 2. The activity series of metal is M:[\ <]YL^:_:^` , ZKf]
24
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------Practice the following Diagrams 1. We know the ratio of Hydrogen and oxygen in water is 2:1, what type experimental arrangement you prefer in order to prove the above fact? Explain with diagram? (OR) Draw a neat diagram of representation of Electrolysis of water. (Page-33) 2. Draw the diagram of electromagnetic waves and labelled the parts? (Page-161) 3. Draw a neat diagram of sequence of filling up of electrons into an orbital. (OR) Draw a Moeller Chart showing the increasing order of energy levels of various orbitals. (Page-172) 4. Draw a neat diagram of Magnetic separation of enrichment of ore and labelled the parts? (Page-290) 5. Draw the neat diagram of Blast Furnace and labelled the parts. (Page-298) 6. Draw a neat diagram of Reverberatory Furnance and labelled the parts? (Page-298)
Important Physical Quantities and Their Units S.No 1 2
Physical Quantity Heat Temparature
3 4 5 6 7
Specific heat latent heat of vaporization Latent heat of fusion Refractive index Power of lens
dioptre(D)
8
Atomic radius
‘pm’ (pico meter)
9
Ionization energy
10
Electron affinity
11
Bond length
12 13 14 15 16
Bond (dissociation) energy Electric current Potential Difference EMF Resistance
kJ mol-1 (or) K Cal mol-1 (or) ev kJ mol-1 (or) K Cal mol-1 (or) ev nm (nanometer) or Å (Angstrom unit). KJmol-1 coloumb/ second joule/ coulomb joule/ coulomb
17 18 19
Specific resistance(or) resistivity Conductivity (σ). Electric power
20
Electric power consumption
21
Magnetic flux(Φ) Magnetic flux density Magnetic field induction(B)
22
Unit
(or)
S.I Unit joule (J) kelvin (K)(or) celsius (0C). J / kg - K J/kg. J/kg. No units
C.G.S Unit calorie (cal). cal/g-oC cal/gm cal/gm No units
ampere(A) volt(V) volt(V) ohm(Ω) Ω- m. mho-m watt (small unit of power) kilowatt( A bigger unit) KWH (kilo watt hour). weber weber/(meter)2 (or) tesla
Gauss
Important Values of Physical Quantities 1. 1cal = 4.186 joules 2. Temperature in Kelvin = 273 + Temperature in degree Celsius 3. Specific heat of a Lead is 0.031 cal/g-oC 4. Specific heat of a Brass is 0.092 cal/g-oC 5. Specific heat of a Copper is 0.095 cal/g-oC 6. Specific heat of a Ice is 0.50 cal/g-oC 7. Specific heat of a Water is 1 cal/g-oC 8. 1 cal/g- oC = 1 kcal /kg-K = 4.2 x 103J/kg-K 9. The value of Latent heat of vaporization of water is 540 cal/gm. 10. The value of Latent heat of fusion of ice is 80cal/gm. 11. The speed of light in vacuum is 3 x108 m/s. 25
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------12. Refractive indices of air is 1.0003 13. Refractive indices of Water is 1.33 14. Refractive indices of Kerosene is 1.44 15. Refractive indices of Benzene is 1.50 16. Refractive indices of Rock salt is 1.54 17. Refractive indices of Ruby is 1.71 18. Refractive indices of Diamond is 2.42 19. Maximum focal length of a eye lens, fmax = 2.5 cm 20. Minimum focal length of a eye lens, fmin = 2.27 cm 21. Focal length of a convex lens is, f = -D i 22. Focal length of a concave lens is, f= i 23. Plank’s constant value is 6.626 X 10-34Js (or) 6.626 X 10-27 erg s 24. 1 pm = 10-12 m 25. 1 A0 unit = 10-8 cm 26. An angstrom (Å) is a unit of length equal to 10-10 metre, or 0.1 nanometre, or 100 picometre. 27. 1 nanometre = 10-9 metre. 28. The magnitude of electric charge ‘e’ is 1.602 x 10-19 C. 29. The electron density of copper , n = 8.5x1028m–3. 30. Drift speed or drift velocity, vd = 7x10-5 m/s = 0.07mm/s. 31. 1 KW = 36 x 105 J 32. Resistivity of Silver is 1.59 × 10-8 Ω-m 33. Resistivity of Copper is 1.68 × 10-8 Ω-m 34. Resistivity of Gold is 2.44 × 10-8 Ω-m 35. Resistivity of Tungsten is 5.60 × 10-8 Ω-m 36. Resistivity of Iron is 1.00 × 10-7 Ω-m 37. Resistivity of Lead is 2.20 × 10-7 Ω-m 38. Resistivity of Drinking water is 2.00 × 10-1 Ω-m 39. Resistivity of Air is 1.30 × 1016 Ω-m 40. Chemical formula of a rust is Fe2O3.XH2O (Hydrated ferric oxide)
Textual Formulae
j
1. Specific heat, S = k ∆l 2. Principle of method of mixtures is, Net heat lost= Net heat gain. j 3. Latent heat of vaporization is, L = k. j
4. Latent heat of fusion, L = . k
5. Mirror formula, m = n + o 6. Absolute refractive index(n) =
)
0 12 4
)
0 12 0 ( ) 4 0 p ( 0
7. Relative refractive index, ( n21 ) =
4
)
8. Snell’s law, n1 sin i = n2 sin r (or) ) 9. Refrective index of a glass slab = 10. Critical angle, Sin c =
q q
=
4
( )
0 p r (
11. Image formation for curved mirrors,
( q ) (q )
= Constant.
2 s
(( 2 ( 4t
2 s (( ( 4t – 0 p ( 0
4
0 0
0 p r ( 0 q q q q o
-
n
=
.
4 (2 0 ( q ) (q )
v
12. Lens formula is, m = o - n. 13. Lens makers formula is,
m
= (n-1) [
-
]
14. Focal length of a convex lens is, f = -D i 15. Focal length of a concave lens is, f= i 16. Power of lens P = m(wq k) (or) P = m (wq xk) ABC
17. Refractive index of the material of a prism, n =
)
A
)
18. Planck’s equation, E = hν. 19. The maximum number of electrons accommodated in a shell = 2n2. 20. For a given l value, the values of magnetic quantum number, ml = (2l +1) y4 1z 4 r z 21. Electronegativity = 22. Electric current (I) =
{
24 1 (|)
4()
26
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------23. Drift sped of a electrons in a conductor is, vd =
} q~•
24. Ohm’s law , V = IR € 25. Resistance, R = R = ρ . (Where ρ is a specific resistance or resistivity) • 26. Equivalent resistance of three resistors connected in series, Req = R1 + R2 + R3 = + + 27. Equivalent resistance of three resistors connected in papallel, •‚
28. Electrical power, P =
o v
8
(or) P = ε I.
29. Magnetic flux density (B) =
ƒ41
r p (Φ) 4 ( )
30. The force experienced by a charge moving in a magnetic field, F = q v B and F = q v B sin θ. 31. The magnetic force on a current carrying wire which is placedin a magnetic field, F = ILB and F = ILB sinθ. 32. Motional EMF, ε = Blv. „ 33. Irms = * and Vrms = * where I0 and V0 be the peak values of AC and AC - EMF. √
√
Scientists and Their Inventions Scientists
Concepts
1. Pierre de Fermat
2. Sorensen 3. Willebrord Snellius 4. Sir C.V Raman 5. Maxplank 6. Rutherford 7. Maxwell 8. Schrodinger 9. Niels Henrik David Bohr 10. Sommerfeld 11. Erwin Schrodinger 12. Max Karl Ernst Ludwig Planck 13. J.J. Thomson 14. Niels Henrik David Bohr 15. Sommerfeld 16. Lande 17. Ulenbeck and Goudsmith 18. Johann Wolfgang Dobereiner 19. John Newlands 20. Lewis and Kossel 21. Kossel 22. G.N. Lewis 23. Sidgwick and Powell 24. Linus Pauling 25. George Simon Ohm 26. Michel Faraday 27. Albert Einstein 28. Robert F. Curl, Harold W. Kroto and Richard E. Smalley 29. Sumio Lijima 30. Antoine Lavoisier
Fermat Principle pH Scale Snell’s law Raman Effect
Quantum theory Planetary model Electron magnetic theory Wave equation Atomic structure and Quantum theory
Elliptical orbit model Quantum mechanical model of an atom Quantum theory of radiation
Watermelon or plum pudding model. Principal Quantum Number (n) The angular - momentum quantum number (l) The magnetic quantum number (ml) Spin Quantum Number (ms) Law of Triad Theory Newlands’ law of Octaves Electronic theory of valence Ionic bond (electrostatic bond) Covalent bond Valence shell electron pair repulsion theory Valence bond theory, Hybridisation of orbitals. Ohm’s law Laws of electrolysis. Laws of mass equivalence Buckminsterfullerene(C60) Nanotubes Father of Modern Chemistry.
Molecules and Their Shapes S.No
Compound
Shape
1 2 3 4 5 6 7 8
BeCl2 BF3 CH4 NH3 H2O CO2 Pcl3 Pcl5
Linear Trigonal-planar. Tetrahedron Pyramidal V-Shape Linear Pyramidal Trigonal bi-pyramidal 27
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------Important Key Words 1. Humidity:- The amount of water vapour present in air is called humidity. 2. Specific heat:- The specific heat of a substance is the amount of heat required to raise the temperature of unit mass of the substance by one unit. 3. Evaporation:- The process of escaping of molecules from the surface of a liquid at any temperature is called evaporation. 4. Condensation:- The phase change from gas to liquid is called condensation. 5. Endothermic reactions:Reactions in which heat energy is absorbed by the reactants are endothermic reactions. 6. Exothermic reactions:- Reactions in which heat energy is released by the reactants are exothermic reactions. 7. Principal Axis:- The horizontal line passes through the centre of curvature and pole is called principle axis or central axis. 8. Focal length(f):-The distance between the focus and the pole of the mirror is called focal length. 9. Radius of curvature(R):- The distance between pole and centre of curvature is called radius of curvature(R). S 12 2 41 (2† ) 10. Magnification(m):- Magnification (m) = S 12 2 t‡
(2ˆ )
11. Neutralization reaction:- The reaction of an acid with a base to give a salt and water is known as a neutralization reaction. 12. Water of crystallization:- Water of crystallization is the fixed number of water molecules present in one formula unit of salt. 13. Alkali:- The basis dissolve in water is called alkali. 14. Family of salts:- Salts having the same positive o negative radicals belong to a family called a family of salts. 15. Critical angle:- The angle of incidence in the denser medium for which the angle of refraction in the rarer medium is 900 is called 'Critical angle(c)'. 16. Mirage:- Mirage is an optical illusion where it appears that water has collected on the road at a distant place but when we get there we don’t find any water. 17. Lense:- A lens is formed when a transparent material is bounded by two surfaces of which one (or) both surfaces are spherical. 18. Optic centre:- The midpoint of a thin lens is called optic centre of lens (P). 19. Accommodation:- The ability of eye lens to change its focal length is called accommodation of lens. 20. Presbyopia:- Presbyopia is a vision defect when the ability of accommodation of the eye usually decreases with ageing. 21. Power of lens(P):- The reciprocal of focal length is called power of lens. 22. Spectrum:- A group of wave lengths or frequencies is called a spectrum. 23. Aufbau principle:- According to this principle, the electron occupies the orbital having the lowest energy. 24. Hund’s Rule:- Hund’s rule states that electron pairing takes place only after all the available degenerate orbitals are occupied by one electron each. 25. Pauli’s exclusion principle:- Pauli’s exclusion principle states that no two electrons will have all the four quantum numbers same. 26. Dobereiner’s law of triads:- A group of three elements in which atomic weight of middle element is the average of first and third elements. 27. Chemical family:- Group of elements is called a chemical family or element family. 28. Atomic radius:- The distance between the nucleus and outermost shell is known as atomic radius. 29. Ionization Energy:- The energy required to remove an electron from the outer most orbit or shell of a neutral gaseous atom is called ionization energy. 30. Electron affinity:- Electron affinity of an element is defined as energy liberated when an electron is added to its neutral gaseous atom. 31. Electro negativity:- The electro negativity of an element is defined as the tendency of atoms to attract electrons towards itself when it is bonded to the atom of another element. 32. Chemical bond:- The force of attraction between any two atoms or a group of atoms that results a stable entity is called a ‘chemical bond’. 33. Co-ordination Number:- Number of ions of opposite charges that surrounds a given ion in a crystal is known as co-ordination number. 34. Group number:- The number of electrons lost from a metal atom is the valence of its element which is equal to its group number. 35. Cation:- A positively charged ion is called a cation. 36. Anion:- A negatively charged ion is called a anion. 37. Octet rule:- The outer most shell having the eight electrons is called octet rule. 38. Electric current:- Electric current is defined as the amount of charge crossing any cross section of the conductor in one second. 39. Ampere:- If one coulomb of charge crosses any cross section of the conductor in one second, then the electric current flows through that conductor is 1amper. 40. Potential difference:- The work done to move a unit positive charge from one point to another it is called as potential difference or voltage. 28
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------41. emf:- emf is defined as the work done by the chemical force to move unit positive charge from negative terminal to positive terminal of the battery. 42. Volt:- If 1 Joule work is done to move 1 coulomb of positive charge from one point to another, then the electric potential difference between those two points is 1 ‘volt’. 43. Ohm's Law:- The potential difference between the ends of a conductor is directly proportional to the electric current passing through it at constant temperature. 44. Resistance:- The resistance of a conductor is defined as the obstruction to the motion of the electrons in a conductor. 45. Ohm(Ω Ω):- If 1 Ampere of electric current passes between two points of potential differences 1 volt, then the resistance between them said to be 1 ohm. 46. Resistor:- The material which offeas resistance to the motion of electrons is called resistor. 47. Electric shock:- The potential difference exists between one part of the body and another part is called an electric shock. 48. Conductivity:- The reciprocal of resistivity is called conductivity (σ). 49. Electric power:- Electric power is the product of potential difference and the current. 50. Electrical energy:- Electrical energy is the product of power and time. 51. Electric motor:- A motor is a device which converts electrical energy into mechanical energy. 52. Electrical generator:- A generator is a device which converts mechanical energy into electrical energy. 53. Metallurgy:- The process of extraction of metals from their ores is called metallurgy. 54. Minerals:- The elements (or) compounds of the metals that occur in nature in earth crust are called as minerals. 55. Ores:- The minerals from which metals are extracted profitably are known as ores. 56. Allotropy:- The occurrence of same element in two or more different forms is known as allotropy. 57. Buckyballs:- Spherical fullerenes are called buckyballs. 58. Catination:Catination is the phenomenon in which atoms of same elements join together to form a long chain. 59. Functional group:- The characteristic properties of an organic compound depend mainly on an atom or group of atoms in its molecule known as the functional group. 60. Isomerism:- Molecules having the same molecular formula but different structures are called isomers. 61. Glycerol:- Fats are esters of higher fatty acids and the trihydroxy alcohol known as glycerol. 62. Soap:- Soap is a sodium or potassium salt of fatty acids. 63. Saponification:- Alkaline hydrolysis of tristers of higher fatty acids producing soaps is called saponification. 64. CMC:- The particular concentration of a true solution is known as critical micelle concentration. 65. Micelle:- A spherical aggregated of soap molecules in water is called micelle. Note: - 1. Practice the IUPAC names of Carbon compounds list out in our text book. 2. While you are writing the IUPAC names of Carbon compounds take the help of your consultant subject teacher. Note :- The shapes of the molecules are depends on bonding electrons and lone pair of electrons. Obseve the following table for an idea to known about the shape of the molecules. S.No No. of bond pairs 1 2 2 3 3 4 4 3 5 2
No. of loan pairs ------1 2
Bond angle 1800 1200 109028I 107048I 104031I
Shape of the molecule Linear Trigonal-planar. Tetrahedron Triagonal pyramidal V-Shape
Example BeCl2 BF3 CH4 NH3 H2O
Ores and Their Formulae Ore Bauxite Copper Iron Pyrites Magnesite Epsom salt Haematite Rock salt Cinnabar Magnetite Galena Gypsum Lime stone Carnallite
Formula Al2O3 2H2O CuFeS2 MgCO3 MgSO4 7H2O Fe2O3 NaCl HgS Fe3O4 PbS CaSO4 2H2O CaCO3) KCl MgCl2 6H2O
Metal Al Cu Mg Mg Fe Na Hg Fe Pb Ca Ca Mg
29
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------Important Bits Important Bits for 2017 Public Examinations 1. Heat 1. Heat is the form of energy. 2. “Temperature and Heat” to describe the hot and cold. 3. The state of thermal equilibrium denotes a state of a body where it neither receives nor gives out heat energy. 4. Heat is the energy that flows from a hotter to a colder body. 5. The SI unit of heat is Joule (J) and CGS unit is calorie (cal). 6. The amount of heat required to increase the temperature of 1gram of water by 10C is called calorie. 7. 1Cal = 4.186 joules 8. The SI unit of temperature is Kelvin (K). It can also be expressed as degree Celsius (0C). 9. 00C = 273K. 10. Temperature in Kelvin = 273+Temperature in degree Celsius. 11. Temperature measured in Kelvin scale is called absolute temperature. 12. The bodies possess kinetic energy when they are in motion. 13. We know the rise in temperature depends on the nature of the material.
14. The average kinetic energy of the molecules is directly proportional to the absolute temperature. 15. Temperature is a quantity that denotes which body is hotter and which is colder. ‰
16. “Specific heat” of substance, S = Š‹Œ. J/Kg-K. 17. Specific heat gives us an idea of the degree of ‘reluctance’ of a substance to change its temperature. 18. CGS unit of specific heat is cal/g-oC and SI unit of it is J / kg – K. 19. 1 cal/g- oC = 1 kcal /kg-K= 4.2 x 103J/kg-K 20. The oceans behave like heat “store houses” for the earth. 21. Oceans can absorb large amounts of heat at the equator without much rise in temperature due to high specific heat capacity of water. 22. Water has greater specific heat value. 23. Net heat lost= Net heat gain. This is known as principle of method of mixtures. 24. “The process of escaping of molecules from the surface of a liquid at any temperature is called evaporation” 25. Evaporation is a surface phenomenon. 26. The change of phase from liquid to gas that occurs at the surface of the liquid.This process is called
evoparation. 27. The phase change from gas to liquid”.This process is called Condensation. 28. ‘Condensation’ is a warming process. 29. Evaporation is a cooling process. 30. The amount of water vapor present in air is called the humidity of air. 31. The water droplets condensed on such surface are known as dew. 32. The thick mist is called fog. 33. The boiling point of water is 1000C. 34. Consider a liquid of mass ‘m’ requires heat energy ‘Q’ calories to change from its state liquid phase to gas phase. Then Latent heat of vaporization is Q/m. 35. CGS unit and SI unit of latent heat of vaporization is Cal/gm. and J/kg respectively. 36. The boiling point of water at constant atmospheric pressure (1atm) is 100°C or 373K . 37. Latent heat of vaporization of water is 540 Cal/gm. 38. When water or any liquid is heated, the solubility of gases it contains reduces. 39. This process of converting solid into a liquid is called “Melting”. 40. Ice becomes to water .This process takes place at a constant temperature 0°C or 273K. 41. Ice becomes to water at 00C. This temperature is called melting point. 42. The Heat energy required to convert 1gm of solid completely into liquid at a constant temperature is called Latent heat of fusion. 43. Latent heat of fusion L = Q/m. 44. The value of Latent heat of fusion of ice is 80cal/gm. 45. The process in which the substance in liquid phase changes to solid phase is called freezing.” 46. If two different systems, A and B, (thermal contact) are in thermal equilibrium individually with another system C. then the systems A and B are in thermal equilibrium with each other. 47. The specific heat capacity of a material is the amount of heat required to raise the temperature of unit mass of the material by or unit. 48. Condensation is the reverse process of evaporation. 49. The Specific heat of a Lead is 0.031 Cal/g-oC. (or) 130 J/kg-K. 50. The Specific heat of a Water is 1 Cal/g-oC 4180 J/kg-K.
30
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------2. Chemical Reactions and Equations 1. The description of chemical reactions in a sentence or it can be written in shorter form as a word equation is called chemical equations. 2. In a chemical reaction the substance present in the left side of the arrow is called reactants. 3. In a chemical reactions the substance present in the right side is called Products. 4. Sometimes during a chemical change may form an insoluble substance known as precipitate. 5. A chemical equation in which the numbers of atoms of different elements on the reactants side (left side) are same as those on product side (right side) is called a balanced reaction. 6. Propane is a colorless, odorless gas often used as a heating and cooking fuel. 7. In some chemical changes heat energy is released. Such chemical reactions are called exothermic chemical reactions. 8. In some chemical changes heat energy is absorbed. Such chemical reactions are called endothermic chemical reactions. 9. In a chemical reaction ‘∆’ represents heating. 10. Sometimes the reaction conditions such as temperature, pressure, catalyst, etc are indicated above and/or below the arrow in the equation. 11. If a gas is evolved in a reaction, it is denoted by an upward arrow ‘↑’or (g). 12. If a precipitatet is forms in a chemical reactions, it is denoted by downword arrow ‘↓’ 13. A chemical equation gives the ratio of molecules of reactants and products. 14. In a chemical equation the molecular masses are expressed in ‘Unified Masses’ (U),. 15. When a decomposition reaction is carried out by heating, it is called thermal decomposition reaction. 16. 1 gram molar mass of any gas at STP i.e, standard temperature 273K and standard pressure 1 bar, occupies 22.4 litres known as gram molar volume. 17. 1 mole of H2 contains 6.02x1023 molecules. 18. The chemical formula of marble is CaCO3 19. Some decomposition reactions are takes place in presence of sunlight and such reactions are called photochemical reactions. 20. A reaction in which single product is formed from two or more reactants is known as chemical combination reaction. 21. chemical combination reaction is a endothermic reactions. 22. All the decomposition reactions require energy in the form of heat, light or electricity for converting the reactants to products. 23. All the decomposition reactions are endothermic. 24. Silver bromide decomposes to silver and bromine in sunlight. Light yellow coloured silver bromide turns to gray due to sunlight. 25. When Zink is reacted with Hydro Chloric Acid, the element zinc has displaced hydrogen from 26. hydrochloric acid. This is displacement reaction. 27. When the iron nail dipped in copper sulphate solution becoming brown. 28. If two reactants exchange their constituents chemically and form two products, then the reaction iscalled as double displacement reaction. 29. ‘Oxidation’ is a reaction that involves the addition of oxygen or removal of hydrogen. 30. ‘Reduction’ is a reaction that involves the addition of hydrogen or removal of oxygen. 31. Generally oxidation and reduction occur in the same reaction. If one reactant gets oxidized, the other gets reduced. Such reactions are called oxidation-reduction reactions or redox reactions. 32. Apples pears, bananas, potatoes etc., contain enzyme called polyphenol oxidase or tyrosinase, which reacts with oxygen and changes the colour on the cut surface of the fruit. 33. The browning of iron, when left for sometime in moist air, is a process commonly known as rusting of iron. 34. Rusting of Iron is basically oxidation reaction which requires both oxygen and water. 35. Rusting does not occur in oxygen free water or dry air. 36. Burning of crackers is also oxidation process of variety of chemicals. 37. When some metals are exposed to moisture, acids etc., they tarnish due to the formation of respective metal oxide on their surface. This process is called corrosion. 38. Corrosion can be prevented by painting, oiling, galvanizing and alloying. 39. Galvanizing is a method of protecting iron from rusting by coating them a thin layer of Zinc. 40. Alloying is also a very good method of improving properties of metal. 41. Iron is mixed with carbon, nickel and chromium to get an alloy stainless steel. 42. Examples of Alloys are Brass, bronze and steel. 43. Combustion is the most common example for oxidation reactions. 44. The metal oxide is an electrical insulator. 45. When fats and oils are oxidized they become rancid. Their smell and taste change. 46. Rancidity is an oxidation reaction. 47. The spoilage of food can be prevented by adding preservatives like Vitamin C and Vitamin E. 48. The manufacturers of potato chips flush bags of chips with nitrogen gas to prevent the chips from getting oxidized. 31
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------3. Reflection of light on different surfaces 1. 2. 3. 4. 5.
A source of light, an opaque object and a screen are needed to form a shadow. Light travels in a straight line. When light gets reflected from a surface, the angle of reflection is equal to the angle of incidence. The incident ray, the normal at the point of incidence and the reflected ray lie in the same plane. Light also selects the path which takes the least time to travel. This principle was first given by Pierre de Fermat, a French lawyer and an amateur mathematician. 6. When light gets reflected from a surface, it selects the path that takes the least time. 7. The plane in which the incident ray, reflected ray and normal will lie is the plane of reflection. 8. The angle plays the role in sensing the size of the object.(The size of the object as angular size) 9. A light ray incident at an angle to the normal at the point of incidence will get reflected making the same angle with the normal. 10. In a concave mirror, all normal’s will converge towards a point. This point is called center of curvature(C)of the mirror. 11. The midpoint (Geometrical center) of the mirror is called pole (P)of the mirror. 12. The horizontal line which passes through the center of curvature and pole is called central axis (Or) principle axis of the mirror. 13. The distance between pole (p) and center of curvature (C) is radius of curvature (R) of the mirror. 14. The rays coming from sun parallel to the concave mirror are converging at a point. This point is called focus or focal point (F) of the concave mirror. 15. The ray passes through principle axis or focus is undeviated. 16. The distance the pole to focal point of the mirror is called the focal length (f) of the mirror. 17. The radius of curvature will be twice of this distance (R=2f). 18. The image that we got by extending the rays backwards is called a virtual image. 19. The image that we cannot get this on a screen like a real image. 20. All distances should be measured from the pole (p). 21. The distances measured in the direction of incident light, to be taken positive and measured in the opposite direction of incident light to be taken negative. 22. The mirror formula is 1/f = 1/u + 1/v. 23. The image formed by a spherical mirror varies in size we refer to the linear magnification ‘m’. 24. The story of Archimedes that he burned ships using mirrors. 25. Light chooses the path which takes the least time to travel. It is also applicable to reflection of light. •:Ž] K• ^\] :ŠY[] Kd•]L^ f:•^Y;L] 26. Magnification, m = (or) m = . •:Ž] K• ^\] Kd•]L^
:ŠY[] f:•^Y;L]
4. Acid Basis and Salts 1. 2. 3. 4. 5. 6.
Acids are sour to taste and turn blue litmus to red. Bases are bitter to taste, soapy to touch and turn red litmus to blue. Methyl orange and phenolphthalein are the examples of synthetic indicators. Litmus solution is a dye extracted from lichen tree. Lichen is a plant belonging to the division of Thallophyta and is used as indicator. There are some substances whose odour changes in acidic or basic media. These are called olfactory indicators. 7. Examples of olfactory indicators are onion, vanilla essence and clove oil. 8. Acid + metal → Salt + hydrogen gas.
9. Metal carbonate + acid → salt + carbon dioxide + water. 10. Metal hydrogen carbonate + acid → salt + carbon dioxide + water.
11. Pickles and sour substances are not stored in brass and copper vessels. 12. The reaction of an acid with a base to give a salt and water is known as a neutralization reaction. 13. Base + Acid → Salt + Water. 14. On dissolving bases in water produces hydroxide (OH-) ions. 15. Bases which are soluble in water are called alkalis. 16. Metallic oxides and metallic haidrates are basic in nature. 17. Non-metallic oxides are acidic in nature. 18. Acid produces the H+ or H3O+ ions in aquous solutions. 19. Basis produces te OH- ions in aquous solutions. 20. The process of dissolving an acid or a base in water is an exothermic process. 21. NaOH is a strong base and dil. NH4OH is a weak base. 22. HCl is a strong acid and CH3COOH is a weak base. 23. Universal indicator is a mixture of several indicators. 24. A scale for measuring hydrogen ion concentration in a solution is called pH scale. 25. The pH of neutral solutions is 7. 26. The pH values less than 7 on the pH scale represent an acidic solution. 32
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------27. The pH value increases from 7 to 14 is Bases. 28. pH value of a solution above ‘7’ represents a basic solution. 29. The pH scale is from 0-14. 30. When pH of rain water is less than 5.6, it is called acid rain. 31. Tooth decay starts when the pH of the mouth is lower than 5.5. 32. To get rid of indigestion pain, people use bases called antacids. 33. Antacids neutralize the excess acid in the stomach. 34. Magnesium hydroxide(milk of magnesia), a mild base, is often used for neutralize purpose. 35. The colour of methyl orange indicator in acidic medium is red. 36. The colour of Phenopthaline indicator in basic solution is pink. 37. The colour of methyl orange indicator in basic solution is yellow. 38. The colour of phenopthaline indicator in acidic solution is colourless. 39. pH paper is called universal indicator. 40. Sodium chloride is also known as table salt or common salt. 41. These deposits of large crystals are often brown due to impurities. This is called rock salt. 42. The aquous solution of sodium chloride is called brain solutions. 43. We get NaOH from NaCl by passing of electricity.The process is called the chlor-alkali process. Because of the products formed chlor for chlorine and alkali for sodium hydroxide. 44. Sodium chloride and water are the raw materials in chloro-alkali process. 45. The chlorine gas is used for the manufacture of bleaching powder. 46. Bleaching Powder is used for bleaching cotton and linen in the textile industry for bleaching wood pulp in paper industry and for bleaching washed clothes in laundry. 47. Baking soda is sometimes added for faster cooking. 48. Baking soda is a mild non-corrosive base. 49. Sodium hydrogen carbonate is an ingredient in antacids. 50. Sodium hydrogen carbonate is is also used in soda-acid fire extinguishers. 51. Chemical formula for hydrated copper sulphate is CuSO4.5 H2O. 52. Calcium sulphate hemihydrates (CaSO4.½ H2O) is called plaster of Paris. 53. The colour of methyl orange indicator in acidic medium is red. 54. The colour of Phenopthaline indicator in basic solution is pink. 55. The colour of methyl orange indicator in basic solution is yellow. 56. The colour of phenopthaline indicator in acidic solution is colourless.
5. Refraction of Light at Plane Surfaces 1. The process of changing speed at an interface when a light travel from one medium to another resulting in a change in direction is refraction of light. 2. The process of refraction involves bending of light ray except when it is incident normally”. 3. If light ray enters from rarer medium to denser medium then refracted ray moves towards the normal drawn at the interface of separation of two media. 4. When light travels from denser medium to rarer medium it bends away from normal. 5. When a light ray propagates through one medium to another medium is expressed in terms of refractive index (n). 6. Light travels in vacuum with a speed nearly equal to 3x108 m/s (denoted by letter ‘c’). 9‘]]fK•#:[\^:;_YLeeŠ(J) 7. Absolute refractive index, n = 9‘]]fK•#:[\^:;Š]f:eŠ(_) 8. Refractive index gives us an idea of how fast or how slow light travels in a medium. 9. Refractive index depends on nature of material and wavelength of light used. •‘]]f K• #:[\^ :; Š]f:eŠ H 10. Refractive index of second medium with respect to first medium is given by,n21= •‘]]f K• #:[\^ :; Š]f:eŠ – I. 11. Relative refractive index, ( n21 ) =
’]•
12. Snell’s law is, n1 sin i = n2 sin r. 13. We observe that at a certain angle of incidence the refracted ray does not come out but grazes the interface separating air and glass. This angle of incidence is known as critical angle(c). H H ; 14. The formula for critical angle is, sin c = ; (Or) 9:; L=;I . HI
H
15. When the angle of the incidence is greater than critical angle, the light ray gets reflected into the denser medium at the interface i.e., light never enters the rarer medium. This phenomenon is called total internal reflection. 16. Mirage is an optical illusion where it appears that water has collected on the road at a distant place but when we get there, we don’t find any water. 17. If the temperature is decreases then the result density of air increases. 18. We know that refractive index of air increases with density. 19. The shining of diamond is due to total internal reflection. 20. The critical angle of a diamond is very low (24.4o). 21. Total internal reflection is the basic principle behind working of optical fiber. 33
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------22. An optical fiber is very thin fiber made of glass (or) plastic having radius about a micrometer. 23. One Micrometer is equeal to 10-6 m. 24. A bunch of optical thin fibers form a light pipe. 25. When light is entered into optical fiber, the angle of incidence is greater than the critical angle and hence total internal reflection takes place. 26. The distance between the parallel rays in a glass slab is called lateral shift. Œ\:L”;]•• K• ^\] •#Yd 27. The refractive index of a glass slab is calculated by using the formula, = . ^\:L”;]•• K• •#Yd – _]<^:LY# •\:•^
28. When the angle of incidence is greater than the critical angle, the light ray is reflected into denser medium at interface. This phenomenon is called total internal reflection. 29. Mirages are formed due to total internal reflection. 30. Brilliance of diamond is due to total internal reflection. 31. Optical fibres works on the principle of total internal reflection. 32. Blue of the sky is due to scattering of light. 33. Rainbow id formed due to dispersion of light. 34. The refractive index of air is 1.0003 35. The refractive index of Ice is 1.31 36. The refractive index of Rock salt is 1.54 37. The refractive index of Water is 1.33 38. The refractive index of Kerosene is 1.44 39. The refractive index of Turpentine oil is 1.47 40. The refractive index of Crown glass is 1.52 41. The refractive index of Diamond is 2.42 42. At critical angle of incidence, the angle of refraction is 90o 43. n1 sin i = n2 sin r, is called Snell’s law. 44. Speed of light in vaccum is 3x108 m/s. 45. Total internal reflection takes place when a light ray propagates from denser to rarer medium. 46. The refractive index of a transparent material is 3/2. The speed of the light in that medium is 2x108m/s.
6. Refraction of Light at Curved Surfaces 1. 2. 3. 4. 5. 6.
The line that joins the center of curvature and the pole is called ‘principal axis’. The center of the sphere, of which curved surface is a part, is called as centerof curvature(C). The ray that travels along the principal axis is undeviated. The ray that travels along the pole is undeviated. The point where refracted ray intersects the axis in all the above cases is called the focal point. If the rays move very close to the principal axis, the rays can be treated as parallel and are called paraxial rays. 7. All distances are measured from the pole (or optic center). 8. Distances measured along the direction of the incident light ray are taken as positive. 9. Distances measured opposite to the direction of the incident light ray are taken as negative. 10. The heights measured vertically above from the points on axis are taken as positive. 11. The heights measured vertically down from points on axis are taken as negative. ; ; ; ; 12. The formula for formation of image in the case of a curved surfaces is _I - eH = I ’ H ;
;
13. The formula for formation of image in the case of a plane mirror is I - H = 0. _ e 14. The lens is bounded by at least one curved surface. 15. A lens may have two spherical surfaces bulging outwards. Such a lens is called double convex lens (Biconvex lens) 16. The center of the sphere which contains the part of the curved surface is called center of curvature. 17. The distance between the center of curvature and curved surface is called radius of curvature(R). 18. The midpoint of a thin lens is called optic center (P) of lens. 19. The point of convergence (or) the point from which rays seem to emanate is called focal point or focus. 20. Every lens has two focal points. 21. The distance between the focal point and optic centre is called the focal length(f). 22. The rays passing parallel to the principal axis converge at the focus in the case of convex lens. 23. The rays passing parallel to the principal axis diverge from the focus in the case of concave lens. 24. The ray passing through the focus will take a path parallel to principal axis after refraction. 25. When object is placed beyond the center of curvature (C2), a real, inverted and diminished image is formed on the principal axis between the points F1 and C1. 26. When an object is placed at the center of curvature (C2) on the principal axis, you will get an image at C1 which is real, inverted and the same size as that of object. 27. When an object is placed between center of curvature (C2) and focus (F2), you will get an image which is real, inverted and magnified. The image will form beyond C1. 28. As the image formed is virtual, we can see it with our eyes. 29. The image is real which we can’t see with our eyes but can be viewed if the image is captured on a screen. 34
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------30. A magnified virtual image is formed on the same side of the lens where the object is placed. 31. The particular behaviour of convex lens helps to construct a microscope, which gives a magnified image. H H H 32. Lens formula is • = _ - e. H
H
H
33. Lens makers formula is, • = (n– 1) (’ - ’ ). H
I
34. The convex lens behaves as a converging lens, if it is kept in a medium with refractive index less than the refractive index of the lens. 35. The convex lens behaves like a diverging lens when it is kept in a transparent medium with greater refractive index than that of the lens. 36. An air bubble in water behaves like a diverging lens. 37. A convex lens is placed in water its focal length is increases.
38. The rays from the distant object, falling on the convex lens pass through focus. 39. The ray passing through the pole of the lens is not deviated. 40. The lens which can form real and virtual images is convex.
7. Human Eye and Colourful world 1. 2. 3. 4. 5. 6. 7.
The least distance of the distinct vision is about 25 cm. The maximum angle, at which we are able to see the whole object is called angle of vision. The angle of vision for a healthy human being is about 600. Iris has a small hole in it called pupil. The distance between the lens and retina is about 2.5 cm. The eye-lens forms a real and inverted image of an object on the retina. The retina is a delicate membrane, which contains about 125 million receptors called ‘rods’ and ‘cones’ which receive the light signal. 8. In a receptors of eye rods identify the colour and cones-identify the intensity of light. 9. The maximum focal length of the eye lens is 2.5 Cm. 10. The minimum focal length of the eye lens is 2.27 Cm. 11. The ability of eye-lens to change its focal length is called “accommodation of lens”. 12. Some people cannot see objects at long distances but can see nearby objects clearly. This type of defect in vision is called ‘Myopia’. 13. The defect, in which people cannot see objects beyond far point, is called ‘Myopia’. 14. Myopia is also called near sightednesses. 15. The least distance of distinct vision, the eye lens can form an image on the retina. This distance is called ‘far point’. 16. The point of maximum distance at which the eye lens can form an image on the retina is called ‘far point’. 17. If we can correct myopia then we need to select bi-concave lens. 18. Hypermetropia is also known as “far sightedness”. 19. A person with hypermetropia can see distant objects clearly but cannot see objects at near distances. 20. The minimum focal length of eye lens for the person of hypermetropia is greater than 2.27 cm. 21. The point of minimum distance at which the eye lens can form an image on the retina is called near point (d).
22. To correct the defect of hypermetropia, we need to use a double convex lens. 23. The process of accombation of eye lens decreases in increasing the aging is presbiopia. 24. To correct this type of defect of vision we need bi-focal lenses which are formed using both concave and convex lenses. 25. The degree of convergence or divergence of light rays that can be achieved by a lens is expressed in terms of its power. 26. A triangular glass prism has two triangular bases and three rectangular plane lateral surfaces. 27. The angle between the incident ray and normal is called angle of incidence (i1). 28. The ray which comes out of the outer surface of the prism is called emergent ray. 29. The angle between the plane surfaces any two sides are called the angle of the prism or refracting angle of prism (A). 30. The angle between the incident ray and emergent ray is called angle of deviation (d). 31. The refractive index of a prism by using the formula, n =
$B• ) I $ 9:;( ) I
9:; (
32. The splitting of white light into different colours (VIBGYOR) is called dispersion. 33. We can consider that white light is a collection of waves with different wavelengths. 34. Light is an electromagnetic wave. 35. The refractive index of a medium depends on wavelength of light. 36. Red colour has longest wavelength and violet colour has shortest wavelength. 37. The relation between the speed of wave (υ), wavelength (λ) and frequency (f) is, v= f λ. (Frequency (f) may be denoted by ‘υ’) 38. Speed of the wave increases with increase in wavelength of light. 39. The angle between the incoming and outgoing rays can be anything between 00 and about 420. 40. The beautiful colours of the rainbow are due to dispersion of the sunlight by millions of tiny water droplets. 35
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------41. The rays of sunlight enter the drop near its top surface. At this first refraction, the white light is dispersed into its spectrum of colours, violet being deviated the most and red the least. 42. The atoms or molecules are called scattering center. 43. The intensity of scattered light varies with angle of scattering. 44. The intensity is maximum at 900 angle of scattering. 45. The reason for blue sky is due to the molecules N2 and O2. 46. C.V Raman found experimentally that the frequency of scattered light by the liquids is greater than the frequency of incident light. 47. Raman introduced the Raman Effect. 48. Raman effect is helpful to determine the shapes of the molecules. 49. The defect in which people cannot see objects situated before near point is called Hypermetropia. 50. The reciprocal of focal length is called power of the lens.
8. Structure of Atom 1. The smallest unit of substances is called atom. 2. The central part of an atom is called nucleus. 3. Nucleus is made up of sub atomic particles like electron, proton and neutron. 4. Visible light is an electromagnetic wave. 5. The speed of light (c) is 3 × 108 m/ s. 6. The electromagnetic energy is characterized by wavelength (λ) and frequency (υ). 7. A group of wave length or frequencies is called a spectrum. 8. The familiar example of the visible spectrum in nature is the formation of a rainbow. 9. The range of wavelengths covering red colour to violet colour is called the visible spectrum. 10. The entire range of wavelengths is known as the electromagnetic spectrum. 11. In the equation E = hυ, where ‘h’ is Planck’s constant and ‘υ’ is the frequency of light. 12. The value of h is 6.626 X 10-34 Js (Or) 6.625x 10-27erg.Sec 13. Scientists found that each element emits its own characteristic colour. These colours correspond to certain discrete wavelengths of light and are called line spectra. 14. The states corresponding to these energies are called stationary states and the possible values of the energy is called energy levels. 15. The energy emitted by the electron is seen in the form of electromagnetic energy and when the wavelength is in the visible region it is visible as an emission line. 16. Bohr’s model explains all the line spectra observed in the case of hydrogen atom. 17. Bohr’s model is a successful model as far as line spectra of hydrogen atom is concerned. 18. The line spectrum of hydrogen atom when observed through a high resolution spectroscope appears as groups of finer lines. 19. Bohr’s model failed to account for splitting of line spectra. 20. The nucleus of the atom is one of the principal foci of these elliptical orbits. 21. Somerfield was guided by the fact that, in general, periodic motion under the influence of a central force will lead to elliptical orbits with the force situated at one of the foci. 22. Bohr’s model failed to account for the atomic spectra of atoms of more than one electron. 23. Max Karl Ernst Ludwig Planck was a German theoretical physicist who originated quantum theory, which won him the Nobel Prize in Physics in 1918. 24. Planck made many contributions to theoretical physics, but his fame rests primarily on his role as originator of the quantum theory. 25. Electron revolves around the nucleus in defined paths called orbits or shells. 26. This short wavelength light interacts with the electron and disturbs the motion of the electron. 27. Quantum mechanical model of atom was developed by Erwin Schrodinger. 28. The region of space around the nucleus where the probability of finding the electron is maximum is called an orbital. 29. Each electron in an atom is described by a set of three numbers n, l, and ml.These numbers are called quantum numbers. 30. Quantum numbersindicate the probability of finding the electron in the space around the nucleus. 31. The quantum numbers describe the space around the nucleus where the electrons are found and also their energies. These are called atomic orbitals. 32. Principal quantum number was introduced by Neil’s Bohr. 33. Principle quantum number was denoted by the letter ‘n’ 34. The principal quantum number is related to the size and energy of the main shell. 35. ‘n’ has positive integer values of 1, 2, 3,… 36. As ‘n’ increases, the shells become larger and the electrons in those shells are farther from the nucleus. 37. An increase in ‘n’ also means higher energy. n = 1, 2, 3 ... are often represented by the letters K, L, M…For each ‘n’ value there is one main shell. 38. Each shell or orbit has definite energy. These orbits are called Stationary orbit. 36
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------39. Stationary orbits are denoted by the letters K, L, M, N, O, P…..etc. 40. The angular-momentum quantum number (l) was proposed by Somerfield. 41. ‘l’ has integer values from 0 to n-1 for each value of ‘n’. Each ‘l’ value represents one sub-shell. 42. Each value of ‘l’ is related to the shape of a particular sub-shell in the space around the nucleus. 43. The value of ‘l’ for a particular sub-shell is generally designated by the letters s, p, d . . . 44. l values for s, p, d and f orbitals are 0,1,2 and 3. 45. n values for s, p, d and f orbitals are 1,2 , 3 and 4.
46. When n = 1, there is only one sub-shell with l= 0. This is designated as ‘1s’ orbital. 47. When n = 2, there are two sub-shells, with l= 0, the ‘2s’ sub-shell and with l= 1, the ‘2p’ sub-shell. 48. The magnetic quantum number (ml) quantum number was proposed by Lande. 49. Orbitals in the sub-shell belonging to the same shell possess same energy. 50. S-orbital is spherical in shape, p-orbital is dumbbell-shaped and d-orbital are double dumbbell shape. 51. Each sub-shell holds a maximum of twice as many electrons as the number of orbital’s in the sub-shell. 52. The maximum number of electrons that can occupy various sub-shells is given by the formula 2n. 53. The total number of electrons that can occupy various shell or orbit was given by the formula 2n2. 54. Spin Quantum Number (ms) was introduced by Uhlen beck and Goldsmith. 55. According to Pauli Exclusion Principle no two electrons of the same atom can have the entire four quantum numbers same. 56. According to Aufbau principle, the electron enter into lowest-energy orbital’s first. 57. According to Hund’srule, the electron pairing takes place all the available degenerate orbitals are completely filled by one electron in each.The clock wise and anti-clock wise spin of the electron was represented by +1/2 and -1/2. 58. Electrons with paired spins are denoted by ‘↑↓’. 59. The maximum number of electrons in any shell is ‘2n2’, where ‘n’ is the principal quantum number. 60. The maximum number of electrons in a sub-shell (s, p, d or f) is equal to 2(2l+1). 61. Electrons are assigned to orbitals in order of increasing value of (n+l). 62. Spectrum is a group of wavelengths or frequencies. 63. After filling the 3p orbital the electrons are enters into 4s orbital. 64. After filling the 5s orbital the electrons are enters into 4d orbital.
9. Classification of Elements- The Periodic Table 1. The atomic weight of the middle element is the average of the atomic weights of the first and third elements. This statement is called the Dobereiner’s law of triads. 2. Newlands was the first to assign atomic numbers to the elements. 3. Mendeleef arranged the elements known at that time in a chart in a systematic order in the increasing order of their atomic weights. 4. Mendeleef divided the chart into 8 vertical columns known as groups. 5. Mandeleeff periodic table based on atomic weight. 6. There are eight vertical columns in Mendeleef’s periodic table called as groups. 7. Groups are represented by Roman numerals I to VIII. 8. The horizontal rows in Mendeleef’s periodic table are called periods. 9. There are seven periods in the table, which are denoted by Arabic numerals 1 to 7. 10. Eka is a Sanskrit word for numeral one. 11. In his honour of Mendeleeff the 101th element was named as Mendelevium. 12. H.J. Moseley (1913) found that each element emits a characteristic pattern of X-rays when subjected to bombardment by high energy electrons. 13. The number of positive charges (protons) in the atom of an element is called the atomic number of the element. 14. Moseley realized that the atomic number is more fundamental characteristic of an element than its atomic weight. 15. The periodic law is changed from atomic weight concept to atomic number concept and now it is called the modern periodic law. 16. The modern periodic table has eighteen vertical columns known as groups and seven horizontal rows known as periods. 17. The elements with similar outer shell (valence shell) electronic configurations in their atoms are in the same column called group. 18. Elements listed in a group down to it are in the order of their increasing principal quantum number. 19. The group of elements is also called element family or chemical family. 20. Group1 (IA) elements are Alkali metal family. 21. Group2 (IIA) elements are Alkali earth metal family. 22. Group 13 (IIIA) elements are Boron family. 23. Group 14 (IVA) elements are Carbon family. 24. Group 15 (VA) elements are Nitrogen family. 25. Group 16 (VIA) elements are Oxygen family or (Chalcogen family). 26. Group 17 (VIIA) elements are Halogen family. 37
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------27. Group 18 (VIIIA) elements are Noble gas family. 28. The ‘4f’ elements are called Lanthanoids or lanthanides. 29. The 5f elements are called Actinides or as Actinides. They are from 90Th to 103Lr . 30. Metalloids or semi-metals are elements which have properties that are intermediate between the properties of metals and non-metals. 31. All elements in s-block are metals, whereas in p-block (except 18th group) there are metals, non-metals and metalloids. 32. The distance between the nucleus and outer most shell is known as atomic radius. 33. Atomic radius is measured in ‘pm’ (pico meter) units. (1 pm = 10-12 m) 34. In general the positive ions are called cation and negative charged ions are called anions. 35. The energy required removing an electron from the outer most orbits or shell of a neutral gaseous atom is called ionization energy. 36. The energy required removing the first electron from the outer most orbits or shell of a neutral gaseous atom of the element is called its first ionization energy. 37. The energy required to remove an electron from uni- positive ion of the element is called the 2nd ionization energy of that element and so on. 38. If the nuclear charge increases then ionization energy is increases. 39. More the shells with electrons between the nucleus and the valence shell, they act as screens and decrease nuclear attraction over valence electron. This is called the screening effect. 40. If more the screening effect, less is the ionization energy. 41. If more the atomic radius, less is the ionization energy. 42. Ionization energy is expressed in kJ mol-1 (or) ev. 43. The electron affinity of an element is defined as the energy liberated when an electron is added to its neutral gaseous atom. 44. Electron affinity of an element is also called electron gain enthalpy of that element. 45. The electro negativity of an element is defined as the relative tendency of its atom to attract electrons towards it when it is bonded to the atom of another element. 46. Milliken proposed that the electro negativity of an element is the average value of its ionization energy and electron affinity. :K;:ŽY^:K; ];]<[` ]#]L^
10. Chemical Bonding 1. 2. 3. 4. 5.
The strength of attraction or repulsion will decide bond formation. If attraction is more than the repulsion then atoms combine. If repulsion is more than attraction then the atoms do not combine. Noble gases are more stable.Because they have octant configuration. The valence electronic configuration of Inert gases(or noble gases or “O” group elements or 18th group elements) is ns2 np6 except helium (1s2) 6. All the noble gases have eight electrons in the outermost shell, except Helium (He). 7. The valence electron in the atom of an element is depicted in a short form by Lewis symbol or electron dot structure. 8. Electronic theory of valence was given by Lewis and Kossel in 1916. 9. Atoms combine to form a molecule. 10. The valence shell fill with eight electrons is called octant configuration. 11. The force of attraction between any two atoms or a group of atoms that results a stable entity is called a ‘chemical bond’. 12. Sometimes based on the forces being electrostatic, the bond is also called the electrostatic bond. 13. As the valence concept has been explained in terms of electrons, it is also called the electrovalent bond. 14. The electrostatic attractive force that keeps cation and anion together to form a new electrically neutral compound is called ‘ionic bond’. 15. Generally elements of metals have tendency of losing electron to attain the octet in their valence shell. This property is called as the metallic character or electro positivity. 16. Elements with more electropositive character form cations. 17. The electrons shared between two atoms belong to both the atoms and the sharing of electrons between them leads to the formation of a chemical bond known as covalent bond. 38
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------18. Bond length or bond distance is generally given in nm (nanometer) or Å (Angstrom unit). 19. An angstrom (Å) is a unit of length equal to 10-10meter, or 0.1 nanometer, or 100 picometre. 20. 1 nanometer = 10-9meter (Or) 1Ao= 10-8 cm. 21. Valence – shell – electron – pair repulsion – theory (VSEPRT) was proposed by Sedgwick and Powell. 22. Valence – shell – electron – pair repulsion – theory (VSEPRT) was further improved by Gillespie and Nyholm (1957). 23. If two bond pairs are present in two covalent bonds around the nucleus of the central atom without any lone pairs in the valence shell, they must be separated by 1800 to have minimum repulsion between them. 24. The valence shell separated by the angle 1800 .Thus, the molecule would be linear. 25. If three bond pairs are there in three covalent bonds around the nucleus of the central atom, without 0 any lone pairs they get separated by 120 along three corners of a triangle. 26. The valence shell separated by the angle 1200 . Therefore, the shape of the molecule is trigonal-planar. 27. If there are four bond pairs in the valence shell of the central atom, the four bond pairs will orient along the four corners of a tetrahedron and the bond angle expected is 109028/ 28. The shape of the NH3 molecule is triagonal pyramidal with N at the apex of the pyramid. 29. Water molecules haveV-Shape. 30. To describe covalent bonding, a quantum mechanical model called valence bond theory has been suggested by Linus Pauling (1954). 31. Carbon dioxide has linear shape. 32. In end-on-end overlap Sigma bond(σ) is formed. 33. In side-on overlap pi (Π) bond is formed. 34. Sigma bond is stronger than pi-bond 35. In chlorine molecule one sigma bond is formed. 36. In nitrogen molecule one sigma and two pi-bonds are formed. 37. In oxygen molecule one sigma-bond and one pi-bond is formed. 38. Hybridization of atomic orbital’s’ was proposed by Linus Pauling (1931). 39. Hybridization is a phenomenon of intermixing of atomic orbital’s of almost equal energy which are present in the outer shells of the atom and their reshuffling or redistribution into the same number of orbital’s but with equal properties like energy and shape. 40. Borontriflouride (BF3) has planar triangular shape. 41. Ammonia (NH3) has pyramidal shape. 42. Shape of water (H2O) molecule is v-shape. 43. Sp hybridization is formed in Beryllium chloride. 44. sp2 hybridization is formed in Boron triflouride. 45. sp3 hybridisation is formed in ammonia and water molecules. 46. Ionic compounds like NaCl are solids at room temperature. 47. Ions are positively or negatively charged particles formed by the loss or gain of electrons. 48. The outer most shell is called valence shell and electrons in this are called valence electrons. 49. The reason why atoms bond can be explained on the basis of the octet rule. 50. Chemically active elements have an incomplete octet in their valence shell of the atoms. 51. The number of valence electrons available in the atoms decides the type of bond. 52. Elements which have tendency to gain electrons for attaining octet in their valence shell called electro negative character elements. They form anions. 53. Ionic compounds are often crystalline solids with high melting points. 54. The H –H bond length is 0.74AO and Bond (dissociation) energy is 436 KJmol-1 55. The F – F bond length is 1.44AO and Bond (dissociation) energy is 159 KJmol-1 56. The Cl– Clbond length is 1.95AO and Bond (dissociation) energy is 243 KJmol-1 57. The Br – Br bond length is 2.28AO and Bond (dissociation) energy is 193 KJmol-1 58. The I – I bond length is 2.68AO and Bond (dissociation) energy is 151 KJmol-1 59. The H – F bond length is 0.918AO and Bond (dissociation) energy is 570 KJmol-1 60. The H – Clbond length is 1.27AO and Bond (dissociation) energy is 432 KJmol-1 61. The H – Br bond length is 1.42AO and Bond (dissociation) energy is 366 KJmol-1 62. The H – I bond length is 1.61AO and Bond (dissociation) energy is 298 KJmol-1 63. The H – O (of H2O) bond length is 0.96AO and Bond (dissociation) energy is 460 KJmol-1 64. The H – N (of NH3) bond length is 1.01AO and Bond (dissociation) energy is 390 KJmol-1 65. The H – C (of CH4) bond length is 1.10AO and Bond (dissociation) energy is 410 KJmol-1
11. Electric Current 1. 2. 3. 4. 5.
AC stands for Alternative current. DC stands for Direct current. Lightning is an electric discharge between two clouds or between cloud and earth. The electric discharge through air appears to us as an electric spark or lightning. In a battery the chemical energy is converted into electrical energy. 39
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------6. The material which transfers energy from battery (source) to the bulb is called a conductor. 7. The material which cannot transfer energy from battery (source) to the bulb is called a non-conductor. 8. Metals contain a large number of free electrons while the positive ions are fixed in their locations. 9. The arrangement of the positive ions in a conductor is called lattice. 10. The ordered motion of electrons in a conductor is called electric current. 11. Electric current is defined as the amount of charge crossing any cross section of the conductor in one second. ]#]L^<:L L\Y<[] ‰ 12. Electric current, I = ^:Š] :;^]<_Y# ( I= ^ ). 13. The SI unit of electric current is ampere denoted by A. 14. 1 Ampere = 1 Coloumb/1 Second (1 A = 1 C/s). 15. The electrons in the conductor move with a constant average speed. We call this speed as driftspeed or drift velocity. 16. The number of charges present in the conductor in a unit volume is called charge density. 17. The charge carriers in a conductor are electrons. 18. The magnitude of electric charge ‘e’ is 1.602 x 10-19C. 19. The electron density of copper that was found experimentally is n = 8.5x1028m–3. 20. Potential difference is also called voltage. 21. The SI unit of potential difference is “Volt” and it is denoted by V. 22. 1 Volt = 1 Joule/1 Coulomb (1V = 1J/C). 23. A battery consists of two metal plates called electrodes and a chemical (electrolyte). 24. The electrolyte (chemical) between the two metal plates consists of positive and negative ions which move in opposite directions. 25. W/q is the work done by the chemical force on unit negative charge to move it from positive terminal to negative terminal. This is called emf (ε). 26. Generally a volt meter is used to measure potential difference or emf across an electric device like battery. 27. Current is measured in Amperes. 28. The device used to measure the current in the circuit is Ammeter. 29. Ammeter is always connected in series connection in an electric circuit. 30. Volt meter is always connected in parallel connection in an electric circuit..
31. Ohm’s law was introduced by German Physicist, George Simon Ohm. 32. The SI unit of resistance is ohm. The symbol of ohm is Ω. 33. 1 Ohm = 1 Volt/1 Ampere (1 Ω = 1V/A ) 34. The conductors which obey the Ohm’s law are called ohmic conductors. 35. All the metals are examples of Ohmic conductors. 36. The conductors which do not obey the ohms law are called non-ohmic conductors. 37. LED or semiconductors are the examples of non-Ohmic materials. 38. Ohm’s law is not applicable to gaseous conductors. 39. Ohm’s law is not applicable semiconductors such as germanium and silicon. 40. The obstruction of motion of electrons in a conductor called resistance. 41. The material which offers resistance to the motion of electrons is called resistor. 42. The disturbance inside the body due to the passing of the current is felt as electric shock. 43. If the current passing through the body reaches 0.07A, it effects the functioning of the heart and if this much current passes through the heart for more than one second it could be fatal. 44. The electric shock is a combined effect of potential difference, electric current and resistance of the human body. 45. A multi meter is an electronic measuring instrument that combines several measurement functions in one unit. 46. The filament in a bulb acts an s a resistance. 47. The bulb filament made up of tungsten. 48. The resistance of a conductor depends on the material of the conductor. 49. In the equation R = ρ . Here ‘ρ’ is called specific resistance or resistivity. 50. The SI unit of resistivity is Ω - m. 51. The unit of resistance is Ohm (Ω). 52. The reciprocal of resistivity is called conductivity (σ). 53. Metals with low resistivity behave as good conductors. 54. A closed path created by the connecting wires through a battery along which electrons can flow is called a electric circuit. 55. The resistors are connected in series combination the resultant resistance is equeal to sum of individual resistances. (R=R1+R2+R3). 56. 4Ω and 6Ω are connected in series then resultant resistance is 10Ω Ω.
57. The resistors are connected in parallel combination the resultant resistance is equeal to sum of reciprocals of individual resistances.(R = + + or R = 8 ). 8
8
58. Alloys like Nichrome is made from Nickel, chromium and iron. 40
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------59. Alloys like Manganese is made from 86% copper, 12%manganese and 2% nickel. 60. 1 KW = 1000 W = 1000 J/S. 61. 121. The unit of electric power consumption is equal to 1 KWH (one Kilo Watt Hour). 62. 1 KWH = (1000 J/S) (60 x 60 S) = 3600 x 1000 J= 3.6 x 105 J 63. The electric appliances at our home are in parallel connection. 64. Total current drawn from the mains is equal to the sum of the currents passing through each device is called Junction law. 65. The minimum and maximum limitof current that can be drawn from the mains is 5 – 20A. 66. The maximum current that we can draw from the mains is 20A. 67. When the current drawn from the mains is more than 20A. This is called over loading. 68. All the electric devices are saved from damage that could be caused by overload.We can save the house holding wiring and devices by using fuses.
12. Electromagnetism 1. The unit of magnetic field strength is named Oersted in his honour. 2. Oersted was made a foreign member of the Royal Swedish Academy of Sciences in 1822. 3. We say that the magnetic field is three dimensional i.e., magnetic field surrounds its source such as bar magnet. 4. The magnetic lines are formed around the magnet is technically called “magnetic field lines”. 5. The number of lines passing through the plane of area ‘A’ perpendicular to the field is called magnetic flux. It is denoted by ‘Φ’. 6. Magnetic flux represents the number of lines passing through the imagined plane in the field. Flux depends on the orientation of the plane in the field. 7. The S.I unit of magnetic flux is Weber. 8. The strength of the field is technically called magnetic flux density (B). 9. Magnetic flux density is defined as the magnetic flux passing through unit area taken perpendicular to the field. 10. B is also known as magnetic field induction. 11. The ratio of magnetic flux passing through a plane perpendicular to the field and the area of the plane is called the magnetic flux density. 12. So magnetic flux density = magnetic flux/ area. ( B = Φ/A. ⟹Φ = BA) 13. The unit of magnetic flux density is Weber/ (meter)2. It is also called Tesla. 14. B = magnetic flux /effective area. 15. When the current in the coil is in clock-wise direction, the direction of magnetic field due to the coil points away from you. 16. When you curl your right hand fingers in the direction of current, thumb gives the direction of magnetic field. 17. A solenoid is a long wire wound in a close packed helix. 18. The magnetic field lines set up by solenoid resemble those of a bar magnet indicating that a solenoid behaves like a bar magnet. 19. The direction of the field due to solenoid is determined by using right hand rule. 20. One end of the solenoid behaves like a north pole and other behaves like a south pole. 21. The field lines outside the solenoid are continuous with those inside. 22. Outside the solenoid the direction of the field lines is from north to south while inside the direction is from south to north. 23. Themagnetic field lines are closed loops. 24. The current carrying wires produce magnetic field. 25. The electric charges in motion produce magnetic fields. 26. The value of magnetic force on the moving charge can be found experimentally and it is given by, F = q v B. 27. Magnetic force on the charge is the product of three quantities charge, speed and magnetic flux density. 28. When charge moves parallel to the magnetic field the value of θbecomes zero. 29. The direction of magnetic force is always perpendicular to the direction of both velocity and magnetic field. 30. According to right hand rule “If the fore-finger points towards the direction of velocity of chargeor current, middle finger points to the direction of field (B), then thumb gives direction of force. 31. Electric current is charges in motion. 32. To understand the working of an electric motor we need to understand the behaviour of a current carrying coil kept in a uniform magnetic field. 33. Apply right hand rule to get the direction of magnetic force. 34. In electric motors, electrical energy is converted into mechanical energy. 35. When a bar magnet is pushed towards a coil with its north pole facing the coil an induced current is set up in the coil. 36. Whenever there is a continuous change of magnetic flux linked with a closed coil, a current is generated in the coil. 41
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------37. The current generated is called induced current and is set up by an induced electromotive force. 38. The phenomenon of getting induced current is called electromagnetic induction. 39. Faraday observed that the changes in the magnetic flux through the coil are responsible for the generation of current in the coil. 40. Faraday observed that the rapid changes in flux through coil generate greater induced current or induced EMF. 41. The induced EMF generated in a closed loop is equal to the rate of change of magnetic flux passing through it. 42. Induced EMF = change in flux/ time (ε = ∆Φ/∆t). 43. Lenz’s law states that “the induced current will appear in such a direction that it opposes the changes in the flux in the coil.” 44. The tape recorder which we use to listen to songs (or) record voices works on the principle of electromagnetic induction. 45. The tape recorder tape consists of a piece of plastic tape coated with iron oxide. 46. The principle of electromagnetic induction in the case of using ATM card. 47. An induction stove works on the principle of electromagnetic induction. 48. In an AC motor commutator is not necessary. 49. In a DC motor commutator is necessary to reversing the current. 50. In generators, mechanical energy is converted into the electrical energy. 51. Magnetic flux density (B) is defined as the ratio of flux passing through a plane perpendicular to field and the area of the plane. 52. In electric motor, electrical energy is converted into mechanical energy. 53. Faraday’s law: The induced EMF generated in a closed loop is equal to the rate of change of magnetic flux passing through it. 54. Lenz’s law: the induced current set up in the coil is in such a direction that it opposes the changes in the flux. 55. When a conductor of length ‘l’ moves perpendicular to field B with a speed v then potentialdifference (voltage) developed between the ends of conductor is Blv. This EMF is called motional EMF.
13. Principles of Metallurgy 1. 2. 3. 4. 5. 6. 7. 8.
Metallurgyis the process of extraction of metals from their ores. Bronze is an alloy of copper and tin. The elements or compounds of the metals which occur in nature in the earth crust are called minerals. The minerals from which the metals are extracted without economical loss are called ores. 50–70 % of aluminiumoxide is extracted from Bauxite. You will notice that the ores of many metals are oxides and sulphides. The impurities like clay in a ore is called gangue. Froth floatation method is mainly useful for sulphide ores which have no wetting property whereas the impurities getwetted. 9. If the ore or impurity, one of them is magnetic substance and the other non-magnetic substance they are separated using electromagnets. 10. Arrangement of the metals in decreasing order of their reactivity is known as activity series. 11. Sulphide ores are converted into oxides by heating them strongly in excess of air. This process is known as roasting. 12. Thermite process involves the reaction of metal oxides with aluminium. 13. Sodium, calcium, aluminium etc. are highly reactive metals and are used as reducing agents. 14. The reaction of Iron oxide (Fe2O3), with aluminium is used to join railings of railway tracks or cracked machine parts. This reaction is known as the thermite reaction. 15. The chemical formula of cinnabar is HgS. 16. When cinnabar (HgS) which is an ore of mercury. 17. The process of obtaining the pure metal from the impure metal is called refining of the metal. 18. Distillation method is very useful for purification of low boiling metals like zinc and mercury containing high boiling metals as impurities. 19. The extracted metal in the molten state is distilled to obtain the pure metal as distillate. 20. Blister copper is purified by Poling method. 21. In an electrolytic refining method, the impure metal is made to act as anode. 22. In metallic corrosion, a metal is oxidized by loss of electrons generally to oxygen and results in the formation of oxides. 23. Corrosion of iron (commonly known as rusting) occurs in presence of water and air. 24. To prevent corrosion of metals by covering the surface with paint or by some chemicals like bisphenol. 25. Alloying is a method of improving the properties of a metal. 26. When iron is mixed with nickel and chromium we get stainless steel which will not rust. 27. Pure gold is not suitable for making jewellery. 42
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------28. Smelting is a pyrochemical (pyre = heat) process, in which the ore is mixed with flux and fuel and strongly heated. 29. During smelting the impurities (gangue) in the ore react with flux to form slag which is removed. 30. Roasting is a pyrochemical process in which the ore is heated in the presence of oxygen or air below its melting point. 31. Calcinations are a pyrochemical process in which the ore is heated in the absence of air. 32. Flux is a substance added to the ore to remove the gangue from it by reacting with the gangue. 33. Furnace is the one which is used to carry out pyrochemical processes in metallurgy. 34. Chimney is the outlet through which flue (waste) gases go out of the furnace. 35. A metallic compound occurring in the earth crust along with impurities is called mineral. 36. A mineral from which a metal can be extracted economically and conveniently is called ore. 37. The impurity present in the ore is called gangue. 38. The substance added to the ore to remove gangue from it is called flux. 39. Calcinations are a process of heating the ore strongly in the absence of air or oxygen. 40. During calcinations, carbonate is converted to its oxide. 41. Roasting is a process of heating the ore strongly in a free supply of air or oxygen. 42. Calcinations and Roasting are carried out in a reverberatory furnace.
14. Carbon and its Compounds 1. 2. 3. 4. 5.
Carbon has four electrons in the valence shell. Each carbon atom has four unpaired electrons when excited and tends to form four covalent bonds. The bond angle in methane (CH4) is 109o281. The concept of hybridization was introduced by Linus Pauling (1931). The redistribution of orbital’s of almost equal energy in individual atoms to give equal number of new orbitals with identical properties like energy and shape is called “hybridization”. 6. In the hybridization the newly formed orbital’s are called as ‘hybrid orbital’s.’ 7. S-orbital’s overlap with another S-orbital in end-on-end overlap to form Sigma bond (σ σ). 8. P-Orbital’s overlap with another P-Orbital in sideways to form Pi-bond (Π Π). 9. The property of an element to exist in two or more physical forms having more or less similar chemical properties but different physical properties is called allotropy. 10. The different forms of the element are called allotropes. 11. The occurrence of same element in two or more different forms is known as allotropy. 12. Carbon in solid phase can exist in three crystalline allotropic forms: diamond, graphite and buckminsterfullerene(C60). 13. In diamond each carbon atom undergoes in its excited state sp3 hybridization. 14. In a diamond carbon atoms are in tetrahedral arrangement. 15. Due to the hardness of the diamond, it is used as glass cutter. 16. The density of a diamond is 3.51 gm/cc3. 17. The refractive index of a diamond is 2.41. 18. Diamond is a bad conductor of Electricity. 19. Bond length in a diamond is 1.54 Ao. 20. The bond angle in a diamond is 109o 281. 21. Graphite forms a two dimensional layer structure with C-C bonds within the layers. 22. In the layer structure ofgraphite, the carbon atoms are in a trigonalplanar environment. 23. In the graphite carbon atoms are sp2hybridization. 24. Graphite is good conductor of electricity and insoluble in any solvent. 25. The density of graphite is 2.25 gm/cc3. 26. In graphite the carbon atoms are in hexagonal arrangement. 27. The distance between the two carbon atoms ina graphite is 3.35 Ao. 28. In graphite, the distance between the two carbon atoms is 1.42 Ao and its bond angle 120o. 29. The buckminsterfullerene was discovered in 1985 by a team of scientists, Robert F. Curl, Harold W.Kroto and Richard E. Smalley from Rice University and they awarded the 1996 Nobel Prize in Chemistry. 30. They are named so for the resemblance of their structure to the geodesic structures devised by the scientist and architect Richard Buckminster “Bucky” Fuller. 31. Spherical fullerenes are also called buckyballs. 32. Fullerene, 60C molecule contains 12 pentagonal and 20 hexagonal faces on its soccer ball shape, and each carbon atom has sp2 hybridized orbitals. 33. Nanotubes are another allotropic form of carbon discovered in 1991by Sumio li jima. 34. Graphene is extracted from graphite, the material used in pencils. 35. For a thickness of 1mm graphite contains some 3 million layers of graphene. 36. Graphene conducts electricity better than copper. 37. Grapheneis 200 times strongerthan steel but six times lighter. It is almost perfectly transparent to light. 43
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----------------Prepared by Gali Sreekar ,M.Sc.,B.Ed., Chirala Md. , Prakasam Dt. --------------38. J. J. Berzelius (1807) named the compounds that derived from living organism as organic compounds and those from non-living materials as inorganic compounds. 39. F. Wohler (1828) produced an organic compound Urea in the laboratory by heating an inorganic salt ammonium cyanate. 40. Chemical formula of Ammonium cyanate is NH4CNO. 41. The chemiclal formula of urea is CO (NH2)2. 42. An atom of same element join to form a long chain is known as catenation. 43. Open chain hydrocarbonsare also called aliphatic hydrocarbons or acyclic hydrocarbons. 44. All hydrocarbons (both Aliphatic and cyclic hydrocarbons) are again classified as Alkanes, Alkenes and Alkynes. 45. Hydrocarbons containing only single bonds between carbon atoms are called Alkanes. 46. Hydrocarbons containing at least one double bond between carbon atoms are called Alkenes. 47. Hydrocarbons containing at least one triple between carbon atoms are called Alkynes. 48. The hydrocarbons containing only C–C single bonds are known as saturated hydrocarbons. 49. All alkanes are saturated hydrocarbons. 50. The hydrocarbons that contain at least one double bond (C=C) or contain at least one triple bond (C≡C) between the two carbon atoms are called unsaturated hydrocarbons. 51. Alkenes and Alkynes are the examples for unsaturated hydrocarbons. 52. Straight chain, branched chain and closed chain hydro carbon compounds may be saturated or unsaturated. 53. The hydrocarbons that contain –OH group are called alcohols. 54. General formula of alcohols is R – OH where ‘R’ is alkyl group, CnH2n+1. 55. The hydrocarbons with functional group –CHO are called aldehydes. 56. The hydrocarbons with functional group C=O are called ketones. 57. If one hydrogen atom is replaced from NH3 by an alkyl group we get the so called primary amines. 58. If two hydrogen atoms of NH3 are replaced by two alkyl groups (same or different) we get secondary amines. 59. The characteristic properties of an organic compound depend mainly on an atom or group of atoms in its molecule known as the functionalgroup. 60. The common system of the Butane is n-butane. 61. The common system 2-methyl propane is iso-butane. 62. The compounds which are having same molecular formula but different structures are called isomers. 63. The phenomenon of possessing same molecular formula but different properties by the compounds is known as isomerism. 64. The series of carbon compounds in which two successive compounds differ by –CH2 unit is called homologous series. 65. Oxidation reactions may be carried out using oxidizing agents. 66. Fats and oils are both of fatty acids. 67. A reaction in which an atom or a group of atoms in a given compound is replaced by other atom or group of atoms is called a substitution reaction. 68. The process of conversion of starches and sugars to C2H5OH is called fermentation process. 69. Pure ethanol boils at 78.3oC. Pure ethanol is called absolute (100 %) alcohol. 70. Denatured alcohol is ethanol that contains impurities that make it undrinkable. 71. The chemical formula of potassium-di-chromate is K2Cr2O7. 72. K2Cr2O7 is a good oxidizing agent. 73. H2SO4 is a dehydrating agent and removes H2O. 74. Ethanoic acid is commonly called as acetic acid. 5-8% solution of acetic acid in water is called Vinegar. 75. Vinegaris used widely as a preservative in pickles. 76. The strength of acids may be expressed in terms of their pKa values. 77. pKa = -log10Ka 78. The reaction between carboxylic acid and an alcohol in the presence of conc. H2SO4 to form a sweet odoured substance is called esterification. 79. The sodium salts of these higher fatty acids being soaps the reaction is the soap formation reaction which is generally called as saponification reaction. 80. Alkaline hydrolysis of tristers of higher fatty acids producing soaps is called saponification. 81. A colloidal solution contains the solute known as ‘dispersed phase’ with its particles with diameters greater than 1nm but lesser than 1000 nm in the solvent known as ‘dispersion medium’. 82. A spherical aggregate of soap molecules in water is called micelle. 83. Soaps give a true solution at particular concentration known as critical micelle concentration (CMC). 84. When soap is dissolved in water, it forms a colloidal suspension in which the soap molecules cluster together to form spherical micelles. 85. Soap has one polar end and one non-polar end. 86. The non-polar end in soap is hydrophobic, in nature and it is attracted towards grease or oil on the cloth, but not attracted towards water. 44
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