Back to Stans Academy of Chemistry
 
Name: 
 

Quiz on Acid Bases and Buffers



Multiple Choice
Identify the choice that best completes the statement or answers the question.
 

 1. 

Calculate the [H3O+] in 0.010 M HOCl solution. Ka = 3.5 x 10-8.
a.
1.9 x 10-5 M
b.
3.6 x 10-5 M
c.
5.8 x 10-5 M
d.
4.0 x 10-6 M
e.
7.2 x 10-6 M
 

 2. 

In the laboratory, a general chemistry student measured the pH of a 0.599 M aqueous solution of ethylamine, C2H5NH2 (a weak base), to be 12.192. Use the information she obtained to determine the Kb for this base.
a.
2.41 x 10-11
c.
4.15 x 10-4
b.
10-1.88
d.
1.56 x 10-2
 

 3. 

The pOH of an aqueous solution of 0.500 M trimethylamine (a weak base, Kb = 6.3 x 10-5) with the formula (CH3)3N) is:
a.
9.8
b.
7
c.
4.2
d.
2.25
e.
less than 1
 

 4. 

What is the [H3O+] of a solution that is 0.0100 M in HNO2 (Ka = 4.5 x 10-4 ) and 0.0100 M in NaNO2?
a.
2.14 x 10-4 M
b.
1.45 x 10-4 M
c.
7.41 x 10-4 M
d.
4.5 x 10-4 M
e.
1.17 x 10-4 M
 

 5. 

When a weak acid is titrated with a strong base, the pH at the equivalence point is ALWAYS __________.
a.
7
b.
< 7
c.
> 7
d.
< 1
e.
> 4
 

 6. 

Calculate the pH for a buffer solution prepared by mixing 100. mL of 0.10 M HF and 200. mL of 0.10 M KF.
a.
2.82
b.
2.96
c.
3.32
d.
3.44
e.
3.53
 

 7. 

Which of the following aqueous solutions are good buffer systems?
I. 0.20 M calcium hydroxide + 0.20 M calcium chloride
II. 0.35 M ammonia + 0.32 M ammonium nitrate
III. 0.10 M hypochlorous acid + 0.14 M hydrobromic acid
IV. 0.33 M barium iodide + 0.27 M sodium iodide
V. 0.29 M hydrochloric acid + 0.19 M sodium chloride
a.
II III, and IV
b.
II and V
c.
I and IV
d.
II
e.
All would be good buffers
 

 8. 

How many grams of solid sodium acetate should be added to 1.50 L of a 0.287 M acetic acid solution to prepare a buffer with a pH of 4.140 ? Grams sodium acetate = ?
a.
2.43 g
c.
4.14.g
b.
8.77 g
d.
8.00 g
 

 9. 

Which salt dissolved in water will give the highest pH?
a.
NaCl
b.
KBr
c.
NaNO3
d.
NH4Cl
e.
NaF
 

 10. 

The Ka of the weak acid HNO2 is 7.4 x 10-4. What is the Kb of its conjugate base, NO2-?
a.
7.4 x 10-4
b.
1.35 x 103
c.
1.35 x 10-11
d.
1.0 x 10-14
e.
1.8 x 10-5
 

 11. 

What is the pH of 0.10 M sodium acetate (NaAc) solution? The Ka of acetic acid (HAc) is 1.8 x 10-5.
a.
1.0
b.
0.10
c.
7.0
d.
8.9
e.
5.1
 



 
Check Your Work     Start Over
Back to Stans Academy of Chemistry