General Chemistry Principles, Patterns, and Applications, 2011

8. The pK a of Cl 3 CCO 2 H is 0.64. What is the pH of a 0.580 M solution? What percentage of the Cl 3 CCO 2 H is
dissociated?
9. The pH of a 0.150 M solution of aniline hydrochloride (C 6 H 5 NH + 3 Cl − ) is 2.70. What is the pK b of the conjugate
base, aniline (C 6 H 5 NH 2 )? Do you expect the pK b of (CH 3 ) 2 CHNH 2 to be greater than or less than the pK b of
C 6 H 5 NH 2 ? Why?
10. What is the pH of a 0.620 M solution of CH 3 NH + 3 Br − if the pK b of CH 3 NH 2 is 10.62?
11. The pK b of 4-hydroxypyridine is 10.80 at 25°C. What is the pH of a 0.0250 M solution?
12. The pK a values of formic acid and the methylammonium ion are 3.75 and 10.62, respectively. Calculate K for
the following reaction:
13. HCO2 - aq
( ) + CH 3NH 3+ ( aq) HCO2H ( aq) + CH 3NH 2( aq)
14. The pK a values of butanoic acid and the ammonium ion are 4.82 and 9.24, respectively. Calculate K for the
following reaction:
15. CH 3CH 2CH 2CO2 - aq
( ) + NH 4 + ( aq) CH 3CH 2CH 2CO2H ( aq) + NH 3( aq)
16. Use the information in Table 16.2 "Values of " to calculate the pH of a 0.0968 M solution of calcium formate.
17. Calculate the pH of a 0.24 M solution of sodium lactate. The pK a of lactic acid is 3.86.
18. Use the information in Table 16.3 "Values of " to determine the pH of a solution prepared by dissolving 750.0
mg of methylammonium chloride (CH 3 NH 3 + Cl − ) in enough water to make 150.0 mL of solution.
19. Use the information in Table 16.2 "Values of " to determine the pH of a solution prepared by dissolving 855
mg of sodium nitrite (NaNO 2 ) in enough water to make 100.0 mL of solution.
A N S W E R S
1.
2.
3.
4.
5.
6.
Saylor URL: http://www.saylor.org/books
Saylor.org
1496