Download CIS Chemistry

CIS Chemistry
Test Prep Chapter 16 & 17
Acid-Base Equilibrium and Additional Aspects of Aqueous Equilibrium
1. Calculate the pH of a 0.070 M nitric acid solution.
2. Calculate the pH of a 0.0050 M Ca(OH)2 solution.
3. Classify the following salt solutions as neutral, basic, or acidic: KCl, NH4NO3, RbF, AlBr3,
NaC2H3O2
4. Based on their compositions and structures, select the stronger acid in the following pairs:
A. H2SO3 or H2SeO3 B. H3PO4 or H3PO3 C. H2SO3 or H2CO3
5. Identify the Lewis Acid and base in the following:
CN- (aq) + H2O (l)  HCN (aq) + OH- (aq)
6. Calculate the pH of a 0.15M solution of HCN. Ka for HCN is 4.9 x 10-10. What is the percent
ionization for this acid?
7. You have a 0.15 M solution of NH4Br. Kb for ammonia is 1.8 x 10-5. Calculate [H+] and pH of
this solution.
8. Give the definition of a buffer.
9. A solution contains 0.30 mol of acetic acid and 0.25 mol sodium acetate in 1 Liter of solution.
The Ka for acetic acid is….oh, wait a minute….you should know it by now! A. Calculate the
pH of this solution using the common ion effect/box game method. B. Since this problem also
qualifies as a buffer, use the Henderson-Hasselbalch to solve for pH.
10. What are the two characteristics of a buffer?
11. Fred the Chemist is in the lab (YES, again!) working on some titrations. He adds 25.0 mL of
0.100 M NaOH to 45.0 mL of 0.100 M HCl. A.) What is the pH of this solution? B. How
many mL of NaOH would you have to add to reach the equivalence point? C. If you added a
total of 55.0 mL of NaOH, what would the pH be then?
12. In a buffer system that contains 0.600 mol of acetic acid and 0.600 mol of sodium acetate, the
pH is 4.74. Calculate the pH after the addition of 0.050 mol of NaOH.
13. Fred is having so much fun in the lab that he decides to do yet another titration. A.) This time, however, he adds
25.0 mL of 0.10 M NaOH to 40.0 mL of 0.15 M of HC2H3O2. Find the pH of the solution at this point in the
titration. B). How many total mL are needed to reach the equivalence point? What is the pH at this point in the
titration? C) Sketch a titration curve for letter B.
FRED
14. The molar solubility of Lead (II) Bromide at 25˚C is 1.0 x 10-2. Calculate Ksp.
15. a. Calculate the solubility of barium fluoride in pure water, given that the solubility product
constant, Ksp, for this salt is 1.7 x 10-6. b. Calculate the solubility of this salt in a 0.10 M
solution of NaF.
16. Will a precipitate form if 20.0 mL of 0.010 M silver nitrate is mixed with 20.0 mL of 0.050 M
NaCl? The Ksp for silver chloride is 1.8 x 10-10.
17. What are conjugate acid/base pairs? Give two examples, one for a weak acid, and one for a
weak base.
18. Fill out the following table WITHOUT a calculator:
Solution
pH
[H+]
[OH-]
Pure water
0.001 KOH
0.01 M HBr
19. What happens to the solubility of slightly soluble basic salts as the pH of the solution drops?