368
Acid-Base Equilibria
10 A 125 ml sample of 1 00 M NH 4 C1 is added to 50 0 ml of 2 00 M NH 3 What is
the pH of the resulting solution
9
11 What is the pH of the solution that results from the addition of 50 0 ml of 0 100
M NaOH to 50 0 ml of 0 200 M HC 2 H 3 (V
12 What is the pH of the solution that results from the addition of 50 0 ml of 0 100
M NH 3 to 15 0 ml of 0 200 M HCP
13 The pH of each of the following solutions is determined experimentally by pH
meter or by color comparison Calculate the hydrolysis constant for each salt
(a) 0 200 M NH 4 C1 has a pH of 4 97
(b) 0 0100 M KCN has a pH of 10 59
(c) 0 100 M CH 3 NH 3 C1 has a pH of 5 83
(d) 0 100 M KCHO 2 has a pH of 8 38
(e) 0 0100 M LiC 2 H 3 O 2 has a pH of 8 38
14 Calculate the pH of each of the following solutions
(a) 0 400 M NaN 3
(e) 0 250 M (CH 3 ) 2 NH 2 C1
(b) 1 50 M NH 4 NO 3
(f) 0 100 M KNO 3
(c) 0 100 M KF
(g) 0 500 M LiCHO 2
(d) 0 250 M NaCl
(h) 1 00 x 10~
9 M HC1
15 Calculate the pH of the solution resulting from each of the following titration
processes
(a) 50 0 ml of 0 100 M HC1 + 50 0 ml 0 100 M NaOH
(b) 25 0 ml 0 100 M HC1 + 50 0 ml 0 0500 M NH 3
(c) 35 0 ml 0 200 M HCN + 35 0 ml 0 200 M LiOH
(d) 30 0 ml 0 100 M HC 2 H 3 O 2 + 10 0 ml 0 300 M NaOH
16 Select a suitable endpomt indicator for each of the titrations listed in Problem
15
17 If 40 0 ml of 1 00 M HC 2 H 3 O 2 are added to 50 0 ml of 2 00 M NaC 2 H 3 O 2
solution, what will be the pH of the resulting solution
0
18 How would you prepare a solution, using NH 4 NO 3 and NH 3 , so that its pH is
80°
19 You have a buffer solution that contains 1 00 mole of NH 4 C1 and 1 00 mole of
NH 3 per liter
(a) Calculate the pH of this solution
(b) Calculate the pH of the solution after the addition of 0 100 mole of solid
NaOH to a liter
(c) Calculate the pH of this solution after the addition of 0 10 mole of HC1 gas
to a separate one-liter portion of the buffer
(d) Calculate the pH of a solution made by adding 0 10 mole of solid NaOH to
100 ml of water
(e) Calculate the pH of a solution made by adding 0 10 mole of HC1 gas to 100
ml of H 2 O
(f) Compare the answers to (a) through (e) Comment on their significance
Acid-Base Equilibria
10 A 125 ml sample of 1 00 M NH 4 C1 is added to 50 0 ml of 2 00 M NH 3 What is
the pH of the resulting solution
9
11 What is the pH of the solution that results from the addition of 50 0 ml of 0 100
M NaOH to 50 0 ml of 0 200 M HC 2 H 3 (V
12 What is the pH of the solution that results from the addition of 50 0 ml of 0 100
M NH 3 to 15 0 ml of 0 200 M HCP
13 The pH of each of the following solutions is determined experimentally by pH
meter or by color comparison Calculate the hydrolysis constant for each salt
(a) 0 200 M NH 4 C1 has a pH of 4 97
(b) 0 0100 M KCN has a pH of 10 59
(c) 0 100 M CH 3 NH 3 C1 has a pH of 5 83
(d) 0 100 M KCHO 2 has a pH of 8 38
(e) 0 0100 M LiC 2 H 3 O 2 has a pH of 8 38
14 Calculate the pH of each of the following solutions
(a) 0 400 M NaN 3
(e) 0 250 M (CH 3 ) 2 NH 2 C1
(b) 1 50 M NH 4 NO 3
(f) 0 100 M KNO 3
(c) 0 100 M KF
(g) 0 500 M LiCHO 2
(d) 0 250 M NaCl
(h) 1 00 x 10~
9 M HC1
15 Calculate the pH of the solution resulting from each of the following titration
processes
(a) 50 0 ml of 0 100 M HC1 + 50 0 ml 0 100 M NaOH
(b) 25 0 ml 0 100 M HC1 + 50 0 ml 0 0500 M NH 3
(c) 35 0 ml 0 200 M HCN + 35 0 ml 0 200 M LiOH
(d) 30 0 ml 0 100 M HC 2 H 3 O 2 + 10 0 ml 0 300 M NaOH
16 Select a suitable endpomt indicator for each of the titrations listed in Problem
15
17 If 40 0 ml of 1 00 M HC 2 H 3 O 2 are added to 50 0 ml of 2 00 M NaC 2 H 3 O 2
solution, what will be the pH of the resulting solution
0
18 How would you prepare a solution, using NH 4 NO 3 and NH 3 , so that its pH is
80°
19 You have a buffer solution that contains 1 00 mole of NH 4 C1 and 1 00 mole of
NH 3 per liter
(a) Calculate the pH of this solution
(b) Calculate the pH of the solution after the addition of 0 100 mole of solid
NaOH to a liter
(c) Calculate the pH of this solution after the addition of 0 10 mole of HC1 gas
to a separate one-liter portion of the buffer
(d) Calculate the pH of a solution made by adding 0 10 mole of solid NaOH to
100 ml of water
(e) Calculate the pH of a solution made by adding 0 10 mole of HC1 gas to 100
ml of H 2 O
(f) Compare the answers to (a) through (e) Comment on their significance