Acids and Bases
Ka and Kb Worksheet 2
1. Write the chemical equations for the acid ionizations of each of the following weak acids. Write them in terms of H
3
O+. Then write the Ka expressions for each acid. a. HF b. HClO c. HBrO d. HCNO

2. Calculate the Ka for propionic acid, HC
3
H
5
O
2
. The pH of a 0.055 M solution is 3.06M.
3. A solution of 0.20 M hydrazoic acid, HN
3
, has a pH of 3.21. What is the
Ka for this acid?
5. Barbituric acid, HC
4
H
3
N
2
O
3
, is used to prepare various barbiturate drugs.
Calculate the concentrations of hydronium ion and barbiturate ion,
C
4
H
3
N
2
O
3
-
, in a 0.20 M solution of the acid. The Ka= 9.8 x 10
–5
6. A solution of acetic acid that was left over from the vinegar lab in chemistry class was found unlabeled on the shelf. You were able to measure the pH using a pH meter and found it to be 2.68, what is the concentration of the acetic acid?

7. Hydrofluoric acid, unlike hydrochloric acid, is a weak acid. What is the hydronium ion concentration and pH of a 0.040 M aqueous solution of
HF?
8. What is the hydronium ion concentration of a 2.00 x 10 bromobenzoic acid, BrC
6
H
4
-4 M solution of p -
COOH, which has a Ka = 1.00 x 10
–4
? What is the pH of this solution?
9. Write the chemical equation for the base ionization of pyridine, C
5
H
5
N.
Write the Kb expression for pyridine.
10. Trimethylamine, (CH
3
)
2
N, is a gas with a fish ammonia like odor. An aqueous solution that is 0.25 M (CH
3
)
2
N has a pH of 11.63. What is the
Kb for (CH
3
)
2
N.
11. What is the concentration of hydroxide ion in a 0.15 M aqueous solution of hydroxylamine, NH
2
OH? What is the pH?

Quiz/Demos
VII. Acid-Base Properties of Salts: Hydrolysis
A. Definitions