Name:____________________________
Date:______________________
Buffer Homework and Test Review
1. Calculate the pH of each of the following solutions.
a. 0.100 M propanoic acid (HC3H5O2 Ka = 1.3 x 10-5)
b. A mixture containing 0.100 M HC3H5O2 and 0.100 M NaC3H5O2
c. Compare the percent dissociation of the acid in a with the acid in d. Explain the
large difference in the percent dissociation of the acid.
2. Calculate the pH of a solution which is 1.00 M HF and 1.00 M KF. Ka for HF =
7.2 x 10-4
3. Calculate the pH of a solution which is 0.50 M CH3NH2 and 0.70 M CH3NH3Cl.
Kb for CH3NH2 = 4.38 x 10-4
4. Calculate the pH of each of the following buffered solutions.
HC2H3O2
Ka = 1.8 x 10-5
C2H5NH2
Kb = 5.6 x 10-4
a. 0.10 M acetic acid/0.25 M sodium acetate
b. 0.25 M acetic acid/0.10 M sodium acetate
c. 0.50 M C2H5NH2/0.25 M C2H5NH3Cl
d. 0.25 M C2H5NH2/0.50 M C2H5NH3Cl
Part 2: Identify the conjugate acid/base pairs
5. .
6.
.
NH3
+
CH3OH
7. .
OH-
8. .
NH2-
+
+
+

H3O+
NH2-
NH4+

+
CH3O -
H2O
+
H3O+

H2O
+
H2O
H2O

NH3
+
OH-
NH3
Part 3: fill in the following chart
Substance
[H3O+]
HCl
2.50 x 10-2
[OH-]
pH
pOH
5.62 x 104
H2SO4
NaOH
9.82
NH4OH
3.64
9. . What is the pH scale - label
10. What color does litmus paper turn in an acid?
11. What color does bromothymol blue turn in a base?
12. What color does phenolphthalein turn in an acid?
Part 4: Complete and balance the following after predicting products
13. Calcium and hydroiodic acid
14. Copper II carbonate and perchloric acid
15. Magnesium hydroxide and nitrous acid
Part 5: Solve for the molarity of the acid from the following data:
MB = .35 M
MA = ?
VB = 15.4 mL
MAVA = MB VB
VA = 16.3 mL
solve for MA
Part 6: Problems (Show all work!!)
16. Find the Ka of a 0.120M HBr solution if it has a [H3O+] of 4.20 x 10-5
17. Determine the [H2CO3] if the [H3O+] is 4.20 x 10-6M
18. Find the [H3O+] of H3PO4 in a 0.800 M solution (Ka=7.08 x 10-3)
19. What is the [H3O+] of 0.100 M HCOOH? What is the percent ionization?
(Ka = 1.77 x 10-4)
20. A solution has HCN concentration of 1.30 x 10-3 and a KCN concentration of
0.820M. Calculate the hydrogen ion concentration. (Ka = 6.17 x 10-10)
21. What is the [H3O+] in a solution of 0.150M HNO2. Calculate the pH of the
solution and percent ionization. (Ka = 7.24 x 10-4)
22. If 0.030M NaNO2 is added to the solution in question #9, what is the [H3O+], pH
and percent ionization?