PRACTICE PROBLEMS CHM 12

1. A particular vinegar solution has a H3O+ concentration of 0.015 M. What is the pH of the solution?

a) 1.8
b) -1.8
c) 0.015 M
d) 3.3
e) -3.3
2. What is the pOH of the solution in Problem #1?

a) 10.7
b) 17.3
c) 12.2
d) 15.8
e) 7.0
3. The Ka of acetic acid is 1.8 x 10-5. What is its pKa?

a) 1.8 x 10-5
b) 5.18
c) 4.74
d) -4.74
4. What is the pH of a 0.100 M solution of acetic acid?

a) 1.34 x 10-3
b) 2.87
c) 1.00
d) 4.74
e) 3.74
5. What is the acetate ion (Ac- or CH3COO-) concentration of the solution in Problem #4?

a) exactly zero
b) 3.74 M
c) 0.100 M
d) 1.34 x 10-3 M
e) 1.8 x 10-6 M
6. What is the percent ionization of the acetic acid in Problem #4?

a) 1.34%
b) 0.134%
c) 0.0014%
d) 1.8 x 10-5 %
e) 1.8 x 10-3 %
7. What is the pH of 6.0 M aqueous solution of NH3 (ammonia). It's Kb = 1.8 x 10-5.

a) 0.0104
b) 1.98
c) 0.778
d) 12.0
e) 13.2
8. What is the NH4+ concentration of the solution in Problem #7?

a) 6.0 M
b) 0.0104 M
c) 1.8 x 10-4 M
d) 1.8 x 10-5 M
9. HNO2 has a pKa = 3.35 and HOCl has a pKa = 7.45. Which is the stronger acid?

a) HNO2
b) HOCl
10. Based on the information given in Problem #9, what is the Ka of HNO2?

a) 5.25 x 10-1
b) 2.24 x 103
c) 3.5 x 10-3
d) 4.46 x 10-4
e) 1.8 x 10-5
11. What is the H2O species concentration in any dilute aqueous solution?

a) zero
b) infinite
c) 55.5 M
d) 1.0 M
e) 1.0 x 10-7 M
12. Which is the most likely pH of Windex glass cleaner?

a) 2
b) 4
c) 7
d) 12
e) 14
13. A particular vinegar solution has a H3O+ concentration of 0.015 M. What is the pH of the solution?

a) 1.8
b) -1.8
c) 0.015 M
d) 3.3
e) -3.3
14. What is the pH of a 0.10 M solution of HF in water? The Ka = 7.2 x 10- 4.

a) -2.07
b) 8.5 x 10-3
c) 0.10
d) 3.14
e) 2.1
15. What is the percent ionization of the acid in Problem #14?

a) 100%
b) 8.5%
c) 0.11%
d) 0.0011%
e) 0.08%
16. What is the pH of a 0.20 M aqueous solution of the base methylamine, CH3NH2? Kb = 5.0 x 10-4.

a) 2.0
b) 12.0
c) 16.0
d) 10.0
e) 0.01
17. A buffer solution is prepared by the