Chemistry II
HH#23
Acid/Base — Rxns and pH
1. For each of the following acid/base pairs, predict the products of the reaction and decide if the
resulting solution that is formed is weakly acidic, weakly basic or neutral (if equal volumes of equal
concentrations of solution are mixed).
a. HNO3 + NaOH
b. HC2H3O2 + LiOH
c. NH3 + HCl
d. NH4Cl + KOH
e. H2CO3 + 2 NaOH
f. NaF + HBr
g. H2SO4 + 2 KOH
2. What is the pH of
a. a solution with [H+] = 10–4?
b. a 0.1 M HCl solution?
c. a solution with an [OH–] = 10–3?
d. the solution prepared by mixing equal volumes of 1M HCl and 1M KOH?
e. a 0.0005M Ba(OH)2 solution?
3. Calculate the [H+] and [OH–] concentrations of a solution
a. with a pH of 6
b. with a pH of 7
c. with a pH of 10
d. with a pH of 8.5
e. prepared by mixing 1L of 1M HCl and 1 L of 0.5M LiOH
4. The pH of a solution of Ba(OH)2, a strong base, is 10.66 at 25°C. What is the hydroxide ion
concentration in the solution? If the solution volume is 125 mL, how many grams of Ba(OH) 2 must
have been dissolved?
a. A 0.308 g sample of an unknown monoprotic acid is titrated to its endpoint using 19.25 mL of
0.1067 M NaOH (strong base).
b. Determine the moles of the monoprotic acid that were in the sample.
c. What is the molar mass of the acid?
d. What would the molar mass of the acid be if it were diprotic?
Answers:
1.
a.
b.
c.
d.
e.
f.
g.
neutral
basic
acidic
basic
basic
acidic
neutral
2.
a.
b.
c.
d.
e.
4
1
11
7
11
3.
a.
b.
c.
d.
e.
[H+] = 10–6; [OH–] = 10–8
[H+] = 10–7; [OH–] = 10–7
[H+] = 10–10; [OH–] = 10–4
[H+] = 3.16 x 10–9; [OH–] = 3.16 x 10–6
[H+] = 0.25; [OH–] = 4.0 x 10–14
4.
4.57 x 10–4 M; 0.00489 g
5.
a.
b.
c.
0.002054 mol
150 g/mol
300 g/mol