Q4/7/11-D/13 Reg. No

St. Joseph’s College of Arts & Science (Autonomous) St. Joseph’s College Road, Cuddalore – 607001 CH407 – ORGANIC CHEMISTRY - II Time : 3 hrs Max Marks :75

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SECTION – A (20X1=20) Answer ALL Questions I. Choose the correct answer 1. The reagent med is SN i reaction is P

a) SOCl 2 R

2.

P

b) SO 2 Cl 2

R

R

R

R

c) SO 3

R

R

d) H 2 SO 3

R

R

R

R

Elimination reactions are enhanced by a) Strong base

b) High temp

c) Solvent with high ionization energy

d) Both a & b

3. How many Л electrons are present in naphthalene. a) 10

b) 12

c) 6

d) 8

4. The electrophile used is chlorination of benzeneis a) Cl P

P

b) Cl + P

c) Cl 2

P

R

R

d) HCl

5. The IUPAC name for t-butylalcohol is a) 2,2’-dimethyl-1-propanol

b) 2-methyl-2-propropanol

c) 1,1’-dimethyl-2-propanol

d) 1,1’- dimethyl-2-butanol

6. Bakelite is prepared b y a) Kolbe reaction

b) Reimer – Tiemann reaction

c) Laderrer Mananse reaction

d) Coupling reaction

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Q4/7/11-D/13 7. When a molecule loses the energy and changes from S 2 excited R

R

state S 1 excited state, the process is called as R

R

a) Intersystem crossing

b) Fluorescence

c) Internal conversion

d) Phosphorescence

8. Which does not undergo cannizaro reaction a) C 6 H 5 CHO

b) HCHO

c) (Me)3C.CHO

d) C 6 H 5 CH 2 .CHO

R

R

R

R

R

R

R

R

R

R

9. CH 3 COH→ CH 3 COCl. The reagent used is R

R

R

a) PCl 5 R

R

R

b) POCl 3 R

R

c) HCl

d) Cl 2 R

10. Nylon 6:6 is prepared by using a) adipic acid

b) malonic acid

c) Succinic acid

d) Glutaric acid

II. Fill up the blanks 11. SN 2 reactions are controlled by _____ effects. P

P

12. In benzene mechanism, _______ is used as a reagent. 13. Glycol when it is cleaved by HIO 4 ______ is formed. R

R

14. Formaldehyde when it reacts with NH 3 , the product formed R

R

is_____. 15. Pentane – 1,5-dioic acid is _____ III. Match the following 16. Adipic acid

- Inversion of configuration

17. MPV reduction

- Salicylaldehyde

18. Reimer Tiemann reaction

- Polyester

19. Electrophile

- Aluminium isopropoxide

20. SN 2

- SO 3

P

P

R

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SECTION – B (10X2=20) Answer any TEN Questions 21. What are nucleophiles? 22. Why allylchloride prefers SN 1 reaction? P

P

23. Compare basicity and nucleophilicity. 24. What is Huckel’s theory of aromaticity? 25. Give the electrophiles for the following. i) Nitration ii) Sulphonation 26. Using Grignard reagent, how will you prepare alcohol. 27. Starting from glycerol, how will you prepare allyl alcohol? 28. Write Williamson synthesis for the preparation of alcohol. 29. Define singlet state in photochemistry. 30. What is witting reaction? 31. How will you prepare succinic acid from malic acid. 32. Define acidity constant. SECTION- C (5X7=35) Answer any FIVE Questions 33. Explain the mechanism of SN 2 reaction and its stereochemistry. P

P

34. Discuss the effects of nature of substrates on substitution reactions.

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35. Explain the resonance in benzene by molecular orbital theory. 36. Explain reactivity and orientation of various substituents on benzene. 37. Explain the mechanism of the following reaction. i) Reimer Tiemann Reaction ii) Coupling reaction

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38. Explain Norrish type – I and type – II reaction. 39. Explain the following facts. i) Acetic acid is less acidic than phenyl acetic acid ii) Benzoic acid is more acidic than p-toluic acid

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