1. XC Due at the time of SA
1. Which of the following substances is a base when dissolved in water, as defined by Arrhenius?
magnesium sulfate magnesium hydroxide magnesium chloride magnesium acetate
2. In each of the following equations, identify the reactant that is a Brønsted–Lowry acid and the reactant that is a Brønsted–Lowry base:
3. Which of the following sets of chemicals is an acid-base conjugate pair?
HClO2(aq) & ClO2 ¯(aq) H2O(aq) & HClO2(aq)
H3O+(aq) & ClO2 ¯(aq) HClO2(aq) & ClO¯(aq)
4. Write the formula of the conjugate base of each of the following Brønsted–Lowry acids:
HClO3
H2CO3
5. Identify the conjugate acid–base pairs in the following equation:

2. 7. What is the [H3O+] of a solution if [OH−] is 5.0 x 10-8 M?
6. A vinegar solution has a [H3O+] = 2.0 x 10–3 M at 25 °C. What is the [OH–] of the vinegar solution? Is the solution acidic, basic, or neutral?
7. What is the [H3O+] of a solution if [OH−] is 5.0 x 10-8 M?
8. Given that the pH of a solution is 6.7, what is the [H3O+]?
5.0 × 106 M
8.0 × 10-1 M
× 10-7 M
2.0 × 10-7 M

3. 10.8 9. Determine the pH for the following solutions:
[H3O+] = 1.0 x 10–5 M
[H3O+] = 5 x 10–8 M
10.8
10. A solution has a pH of What is the molarity of hydrogen ions in the solution?
11. What is the pH of an ammonia solution at 25 ˚C with [OH–] = 3.7 x 10–3 M?

4. 12. Use the given table to select the acid that fits the following criteria: weak acid stronger than HF(aq).
HCl(aq)
H3PO4(aq)
HNO3(aq)
H2CO3(aq)
13. Which of the following pairs would make a buffer solution?
HF(aq) and NaCl(aq)
HCN(aq) and NaCN(aq)
HBr(aq) and NaCl(aq)
HCl(aq) and LiOH(aq)
14. The acid-base pair in a buffer is H2PO4– /HPO42–, which has a Ka of 6.2 x 10–8. What is the pH of a buffer that is 0.10 M H2PO4– and 0.50 M HPO42–?