Acids and Bases #1

Chemistry 3202

Name:

Acid-Base Theories (Theoretical Definitions) Arrhenius Acids and Bases 1.

Use Arrhenius Theory to write equations that show each of the following are ACIDS.

a)

HNO 2(aq)

b)

CH 3 COOH (aq)

c)

HCN (aq)

d)

HCl(aq)

e)

H 2 SO 4(aq)

2.

Use Arrhenius Theory to write equations that show each of the following are BASES.

a)

CsOH (aq)

b)

Sr(OH)2(aq)

c)

LiOH (aq)

d)

Ca(OH)2(aq)

e)

Al(OH)3(aq)

Modified Arrhenius Theory 3.

Use Modified Arrhenius Theory to write equations for each of the following ACIDS .

a)

HNO 3(aq)

b)

H 2 O (l)

c)

HCO 3 -(aq)

d)

CO 2(g)

Acids and Bases #1

Chemistry 3202

Name:

4.

Use Modified Arrhenius Theory to write equations for each of the following BASES.

a)

NH3(aq)

b)

HCO3-(aq)

c)

CO32-(aq)

d)

S2-(aq)

e)

CN-(aq)

5.

List two Modified Arrhenius acids that CANNOT be Arrhenius acids.

6.

List two Modified Arrhenius bases that CANNOT be Arrhenius bases.

Brønsted-Lowry Acids and Bases 7. Use BLT to identify each reactant and product as an acid or base. NH 4 + (aq)

HNO 2(aq)

+

b)

F -(aq)

NH 4 +(aq)

c)

C 6 H 5 COOH (aq) + CH 3 COO - (aq)

d)

CN -(aq)

e)

H 2 SO 3(aq)

8.

+

+

NH 3(aq)

º

a)

H 2 CO 3(aq) +

SO 3 2-(aq)

º

+

NH 3(aq)

º

+

NO 2 -(aq)

HF (aq)

CH 3 COOH (aq)

º

HCO 3 -(aq)

+

HCN (aq)

X

HSO 3 -(aq)

+

HSO 3 -(aq)

Write the formula of three amphoteric compounds.

+

C 6 H 5 COO -(aq)

Acids and Bases #2

1.

Chemistry 3202

Name:

Strength of Acids & Bases Classify each of the following: Acid or Base

Concentrated or Dilute

Strong or Weak

12.4 mol/L HCl(aq) 0.0100 M HF(aq) 10.5 mol/L CH3COOH(aq) 9.00 mol/L NH3(aq) 0.0500 M NaOH(aq) 2.

Use the Relative Strengths of Acids and Bases Table to identify the stronger acid or stronger base in each pair. a) HClO(aq) or HF(aq) __________ c) HCO3-(aq) or HBO32-(aq) _________ b) SO32-(aq) or CO32-(aq) ________

d) HSO4-(aq) or NO2-(aq) __________

3.

500.0 mL samples of 0.10 M HBr(aq) and 0.10 M HF(aq) solutions are placed in separate beakers. A 0.50 g sample of zinc is added to each beaker. a) What gas will be produced by the reaction of zinc with each acid? _____________ b) In which beaker will the zinc be consumed first? Explain. _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ 4.

Explain which solution will have higher electrical conductivity: 0.100 M HI(aq) or 0.100 M HOOCCOOH(aq)

_____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ 5.

Explain why vinegar, 1.00 mol/L acetic acid, can be consumed without harming your esophagus but 1.00 mol/L HCl(aq) will cause severe damage to your esophagus if consumed. _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ 6.

Use a check (U) to indicate which of the following are amphoteric?

HCO3-

HBO32-

HNO3

F-

CO32-

HSO4-

HPO42-

SO32-

H3PO4

Acids and Bases #2

Chemistry 3202

Name:

Major Species Present in a Water Environment Type of substance

ionic compounds

Solubility in Water high low

molecular compounds

7.

high

Examples Na2 SO4 (s)

Species Present Na+(aq) K+ (aq)

KBr (s) CaCO3 (s) C6 H12 O6

SO4 2-(aq) Br-(aq)

CaCO3 (s) C6 H12 O6

(s)

NH3 (g)

NH3 (aq)

low

C2 H5 OH (l)

C2 H5 OH (aq)

high

weak acids

high

HCl (aq) HNO3 (aq)

H3 O+(aq) H3 O+(aq)

Cl-(aq) NO3 -(aq)

HF (aq)

HF (aq)

CH3 COOH (aq)

CH3 COOH (aq)

Identify the species present when each of the following is placed in water.

a) NaBr (s)

h) C12H22O11 (s)

b) HBr (aq)

i) HClO4 (aq)

c) Ca3PO4 (s)

j) AgCl(s)

d) H2CO3 (aq)

k) H3PO4 (aq)

e) CH3OH (l)

l) HI(aq)

f) Al2(SO4)3 (s)

m) HCN(aq)

g) KNO3 (s)

n) BaSO4 (s)

H2 O(l)

(aq)

or

strong acids

H2 O(l)

H2 O(l)

H2 O(l) H2 O(l)

Acids and Bases #3

Chemistry 3202

Name:

Writing Net Ionic Equations OR Brønsted-Lowry Equations for Acid-Base reactions 5 Step Method • List all species present • Identify the SA and the SB • Write an equation - transfer one proton • Determine reaction type • Determine the position of equilibrium 1. a)

Write the Net Ionic Equation using Brønsted-Lowry theory for each aqueous reaction: sodium carbonate and acetic acid

b)

ammonia and nitrous acid

c)

nitric acid and rubidium hydroxide

d)

sulfuric acid and potassium phosphate

Acids and Bases #3

Chemistry 3202

Name:

e)

hydrofluoric acid and ammonium acetate

f)

calcium chloride and lead sulfate

2.

From the information below, identify the strongest acid and strongest base. Explain your choice. HIO3(aq) + F-(aq)

º

IO3-(aq) + HF(aq)

Keq = 0.0059

__________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ 3.

Write the conjugate acid and/or base for the following:

Conjugate Acid Species Conjugate Base

HCO3-

NO3-

H3PO4

H2PO4-

S2-

H3AsO4

Acids and Bases #4

Formulas:

1.

Chemistry 3202

Kw = [H3O+] [OH-]

Complete the following tables: Acid or Base [H 3 O + ]

Name:

pH = -log [H3O+]

pOH = -log [OH-]

[H3O+] = 10-pH

[OH-] = 10-pOH

[OH -]

pH

pOH

2.00 mol/L nitric acid 2.50 mol/L NaOH(aq) 0.200 mol/L HCl(aq) 0.290 mol/L Sr(OH)2(aq) 6.8 M hydroiodic acid 0.000150 M Mg(OH)2(aq) 0.105 M HBr(aq) 0.175 mol/L Ba(OH)2(aq) 2.00 x 10-3 M HNO 3(aq) 3.11 x 10-3 mol.L-1 KOH 0.0035 M Ca(OH)2(aq) 4.6 mol/L HBr (aq)

[H 3 O + ]

[OH -]

pH

pOH

4.0 x 10-6 mol/L 9.500 2.00 x 10-11 mol/L 10.0 M 15.105 4.4 x 10-2 mol/L -0.48 -1.12 14.00 3.95

Acidic or Basic

Acids and Bases #4

Chemistry 3202

Name:

2.

Calculate the pH and the pOH for each of the following solutions:

a)

10.0 g of NaOH is dissolved to prepare 500.0 mL of solution

b)

25.0 g of HCl is dissolved in 6.00 L of solution

c)

0.500 g of Ca(OH)2 is dissolved to make 4.00 L of solution

d)

40.0 mL of 8.00 mol/L nitric acid is diluted to a final volume of 500.0 mL

e)

20.0 mL of a NaOH solution with a pH = 12.45 is diluted to a final volume of 100.0 mL

3.

Explain how the pH of a HCl(aq) solution changes when the molar concentration increases by a factor of:

a) 10__________________________________________________________________ _________________________________________________________________________ b) 100_________________________________________________________________ __________________________________________________________________________

Acids and Bases #4

Chemistry 3202

Name:

[H3O+] = [strong acid]

Acids and Bases #1

Chemistry 3202

1.

Arrhenius Theory.

a)

HNO2(aq) → H+(aq) + NO2-(aq)

b)

CH3COOH(aq)

c)

HCN(aq)

d)

HCl(aq)

e)

H2SO4(aq) → H+(aq) + HSO4-(aq)

2.

Arrhenius Theory.

a)

CsOH(aq) → Cs+(aq) + OH-(aq)

b)

Sr(OH)2(aq) → Sr2+(aq) + 2 OH-(aq)

c)

LiOH(aq)

d)

Ca(OH)2(aq)

e)

Al(OH)3(aq) → Al3+(aq) + 3 OH-(aq)

3.

Modified Arrhenius Theory.

a)

HNO3(aq) + H2O(l) → H3O+(aq) +

b)

H2O(l)

c)

HCO3-(aq)

d)

CO2(g) + 2 H2O(l) → H3O+(aq) + HCO3-(aq)

4.

Modified Arrhenius Theory.

a)

NH3(aq)

b)

HCO3-(aq) + H2O(l)

→ H+(aq) + CH3COO-(aq)

→ H+(aq) + CN-(aq) → H+(aq) + Cl-(aq)

→ Li+(aq) + OH-(aq) → Ca2+(aq) + 2 OH-(aq)

+ H2O(l) → H3O+(aq) +

NO3-(aq) OH-(aq)

+ H2O(l) → H3O+(aq) +

+ H2O(l)

CO32-(aq)

→ NH4+(aq) + OH-(aq) → H2CO3(aq) + OH-(aq)

Name:

Acids and Bases #1

Chemistry 3202

Name:

c)

CO32-(aq) + H2O(l)

d)

S2-(aq) + H2O(l)

e)

CN-(aq) + H2O(l)

5.

List two Modified Arrhenius acids that CANNOT be Arrhenius acids.

H2O(l) 6.

&

→ HCO3-(aq) + OH-(aq) → HS-(aq) + OH-(aq) → HCN(aq) + OH-(aq)

CO2(g)

List two Modified Arrhenius bases that CANNOT be Arrhenius bases.

Any base from #4. above

7.

Use BLT to identify each reactant and product as an acid or base.

a)

HNO2(aq)

+

NH3(aq)

A b)

F-(aq)

B +

C6H5COOH(aq)

+

CN-(aq)

CH3COO(aq)

e)

H2SO3(aq)

+

→ CH3COOH(aq)

SO32-(aq)

→

B

HCO3-(aq)

+

HCO3-(aq) HSO3-(aq)

+

HCN(aq) A

+

A

H2O(l)

C6H5COO-(aq) B

Write the formula of three amphoteric compounds. HSO3-(aq)

HF(aq) A

B

A

8.

→

A +

B

A

H2CO3(aq)

B

NO2-(aq)

B B

+

+

NH3(aq)

→

A

A d)

NH4+(aq) A

NH4+(aq)

B c)

→

HSO3-(aq) B

Acids and Bases #2

Chemistry 3202

Name:

Strength of Acids & Bases 1.

Classify each of the following: Acid or Base

Concentrated or Dilute

Strong or Weak

12.4 mol/L HCl(aq)

C

S

0.0100 M HF(aq)

D

W

10.5 mol/L CH3COOH(aq)

C

W

9.00 mol/L NH3(aq)

C

W

0.0500 M NaOH(aq)

D

S

2.

Use the Relative Strengths of Acids and Bases Table to identify the stronger acid or stronger base in each pair.

a)

HF(aq)

c)

STRONGER ACID - HCO3-(aq)

3.

500.0 mL samples of 0.10 M HBr(aq) and 0.10 M HF(aq) solutions are placed in separate beakers. A 0.50 g sample of zinc is added to each beaker.

b)

CO32-(aq)

d)

NO2-(aq)

STRONGER BASE - HBO32-(aq)

a) What gas will be produced by the reaction of zinc with each acid? H2(g) b) In which beaker will the zinc be consumed first? Explain. In the beaker with the stronger acid - HBr(aq). In this beaker there is a higher concentration of ions so there will be a faster reaction because ions react faster than molecules and atoms nature of reactants!!

4.

Explain which solution will have higher electrical conductivity: 0.100 M HI(aq) or 0.100 M HOOCCOOH(aq)

In the solution with the stronger acid - HI(aq). In this beaker there is a higher concentration of ions and it is the ions that cause electrical conductivity. 5.

Explain why vinegar, 1.00 mol/L acetic acid, can be consumed without harming your esophagus but 1.00 mol/L HCl(aq) will cause severe damage to your esophagus if consumed.

Again the stronger acid - HCl(aq). In this beaker there is a higher concentration of ions so there will be a faster reaction because ions react faster than molecules and atoms - nature of reactants!!

Acids and Bases #2

6.

7.

Chemistry 3202

Name:

Use a check () to indicate which of the following are amphoteric? HCO3-

HBO32-





HNO3

F-

CO32-

HSO4-

HPO42-





SO32-

Identify the species present when each of the following is placed in water.

a) Na+(aq) & Br-(aq)

h) No Dissociation

b) H3O+(aq) & NO3-(aq)

i)

H3O+(aq) & ClO4-(aq)

c) No Dissociation

j)

No Dissociation

d) No Ionization

k) No Ionization

e) No Dissociation

l)

f)

Al3+(aq) & SO42-(aq)

g) K+(aq) & NO3-(aq))

H3O+(aq) & I-(aq)

m) No Ionization

n)

No Dissociation

H3PO4

species present

Na+(aq) CO32-(aq) CH3COOH(aq) H2O(l) SB CH3COOH(aq) + CO32-(aq)

SA

⇌ CH COO 3

-

+ HCO (aq) 3 (aq)

Weaker Acid

Stronger Acid

Products Favoured 1

species present

NH3(aq)

HNO2(aq)

SB

HNO2(aq) + NH3(aq)

H2O(l)

SA

⇌

Stronger Acid 2

NO2-(aq) + NH4 + (aq) Weaker Acid Products favored

species present

H3O+(aq)

NO3-(aq)

Rb+(aq) OH-(aq)

H2O(l)

strongest acid

strongest base

H3O+(aq) + OH-(aq)

H2O(l) + H2O(l) OR

→ 2 H2O

H3O+(aq) + OH-(aq)

(l)

3

species present + 3+ HSO K PO H3O (aq) 4 (aq) (aq) 4 (aq) SA

H2O(l)

SB

H3O+(aq) + PO43-(aq)

H2O(l) + HPO42-(aq)

4

species present + NH HF(aq) 4 (aq)

CH3COO-(aq)

SA HF(aq) + CH3COO-(aq)

H2O(l)

SB

⇌F

-

Stronger Acid 5

(aq)

+ CH3COOH(aq)

Weaker Acid Products favored

strongest acid

species present

Ca2+(aq) Cl-(aq) Pb2+(aq) SO42-(aq) H2O(l) strongest base

H2O(l) + SO42-(aq)

⇌

Weaker Acid

HSO4-(aq) + OH-(l) Stronger Acid

Reactants favored 6

From the information below, identify the strongest acid and strongest base. Explain your choice. HIO3(aq) + F-(aq) ⇋ IO3-(aq) + HF(aq)

Keq = 0.0059

Because the Keq value is much smaller than 1, reactants are favored. Since the favored side has the weaker acid (and weaker base) the stronger acid and bas are on the right side - IO3-(aq) & HF(aq)

Conjugate Acid Species Conjugate Base

H2CO3

HNO3

H3PO4

HCO3-

NO3-

H3PO4 H2PO4-

CO32-

H2PO4- HPO42-

HS2S2-

H3AsO4 H2AsO4 -

1.

Complete the following tables: Acid or Base

[H3O+]

[OH-]

pH

pOH

2.00 mol/L nitric acid

2.00 mol/L

5.00 x 10-15

-0.301

14.301

2.50 mol/L NaOH(aq)

4.00 x 10-15

2.50 mol/L

14.398

-0.398

0.200 mol/L HCl(aq)

0.200 mol/L

5.00 x 10-14

0.699

13.301

0.290 mol/L Rb(OH)2(aq)

1.72 x 10-14

0.580 mol/L

13.765

0.235

6.8 M hydroiodic acid

6.8 M

1.5 x 10-15

-0.83

14.83

0.000150 M Mg(OH)2(aq)

3.33 x 10-11

0.000300 M

10.478

3.522

0.105 M HBr(aq)

0.105 M

9.52 x 10-14

0.979

13.021

0.175 mol/L Ba(OH)2(aq)

2.86 x 10-14

0.350 mol/L

13.544

0.456

2.00 x 10-3 M HNO3(aq)

2.00 x 10-3

5.00 x 10-12

2.699

11.301

3.11 x 10-3 mol.L-1 KOH

3.22 x 10-12

11.492

2.508

0.0035 M Ca(OH)2(aq)

1.43 x 10-12

3.11 x 10-3 mol.L-1 0.0070 M

11.845

2.155

4.6 mol/L HBr(aq)

4.6 mol/L

2.17 x 10-15

-0.66

14.66

[H3O+]

[OH-]

pH

pOH

Acidic or Basic

4.0 x 10-6 mol/L

2.5 x 10-9 mol/L

5.40

8.60

acidic

3.162 x 10-10 M

3.162 x 10-5 M

9.500

4.500

basic

5.00 x 10-4 mol/L

3.301

10.699

acidic

10.0 M

2.00 x 10-11 mol/L 1.00 x 10-15 M

-1.000

15.000

acidic

7.85 x 10-16 M

12.7 M

15.105

-1.105

basic

2.3 x 10-13 M

4.4 x 10-2 mol/L

12.64

1.36

basic

3.0 M

3.3 x 10-15 M

-0.48

14.48

acidic

7.6 x 10-16 M

13.18 mol/L

15.12

-1.12

basic

1.0 M

1.0 x 10-14 M

0

14.00

acidic

1.1 x 10-4 M

8.9 x 10-11 mol/L

3.95

10.05

acidic

2.

Calculate the pH and the pOH for each of the following solutions:

a)

10.0 g of NaOH is dissolved to prepare 500.0 mL of solution 10.0 g

b)

 divide by M  0.250 mol

[OH-] = 0.500 mol/L

[H3O+] = 2.00 x 10

pOH = 0.301

pH = 13.699



0.6857 mol



-14

0.114 mol/L = [HCl]

[H3O+] = 0.114 mol/L

[OH-] =

pH = 0.943

pOH = 13.057

8.77 x 10-14

0.500 g of Ca(OH)2 is dissolved to make 4.00 L of solution 0.500 g



0.006748 mol



0.00169 mol/L = [Ca(OH)2]

[OH-] = 2 x 0.00169 mol/L = 0.00338 mol/L pOH = 2.471 d)

0.500 mol/L = [NaOH]

25.0 g of HCl is dissolved in 6.00 L of solution 25.0 g

c)

 divide by V 

[H3O+] = 2.96 x 10-12 pH = 11.529

CiVi = CfVf The final concentration of nitric acid is 0.640 mol/L pH = 0.194

e)

pOH = 13.806

If pH= 12.45 then [H3O+] = 3.5 x 10-13 and [NaOH] = 0.028 mol/L = Ci CiVi = CfVf Cf = 0.0056 mol/L pOH = 2.25

3.

pH = 11.75

Explain how the pH of a HCl(aq) solution changes when the molar concentration increases by a factor of:

a)

10

pH decreases by 1

b)

100

pH decreases by 2