Chemistry

Answers to Chapter 16 Study Questions

 

1.

 

[H+]

[OH]

pH

acid, base or neutral?

 

a)

1.0 x 10-4 M

1.0 x 10-10 M

4.0

acid

 

b)

1.0 x 10-7 M

1.0 x 10-7 M

7.0

neutral

 

c)

1.0 x 10-12 M

1.0 x 10-2 M

12.0

base

 

d)

1.0 x 10-3 M

1.0 x 10-11 M

3.0

acid

 

2. a) strong acid, HNO3(aq) H+(aq) + NO3-(aq)

b) weak acid, HF (aq) H+(aq) + F-(aq)

c) weak base, F-(aq) + H2O HF(aq) + OH-(aq)

d) neutral, NaNO3(aq) Na+(aq) + NO3-(aq)

e) strong base, KOH(s) K+(aq) + OH-(aq)

 

3. a) HCl = strong acid; = 1.0 x 10-3 M; pH = 3.0

b) NaOH = strong base; = 0.010 mol/L =

[OH-] = [NaOH] = 1.0 x 10-2 M; [H+] = 1.0 x 10-12 M; pH = 12.0

 

c) HBr = strong acid; 5.0 mL = 5.0 x 10-3 L; V1 x M1 = V2 x M2

(5.0 x 10-3 L) (0.40 M) = (20 L) M2; M2 = (5.0 x 10-3 L) (0.40 M)/(20 L)

M2 = 1.0 x 10-4 M = [H+]; pH = 4.0

 

4. a) It can be an H+ acceptor. b) CH3COOH

c) CH3COO-(aq) + H2O CH3COOH(aq) + OH-(aq)

 

5. a) H+(aq) + OH-(aq) H2O

b) HNO2(aq) + OH-(aq) NO2-(aq) + H2O

c) H+(aq) + HCO3-(aq) H2CO3(aq)

 

6. acids: HNO2 and H2O; bases: OH- and NO2-

 

7. Vb x Mb = Va x Ma; Vb x 2.0 M = 12.5 mL x 0.080 M;

 

8. weakest acid strongest acid: HCN < CH3COOH < HF < HCl

 

9. a) = 0.0150 moles

b) 0.0150 moles

c) 26.1 mL - 2.1 mL = 24.0 mL = 0.0240 L

d) = 0.625 M