Question 1
What is the pH of a solution prepared by mixing 50.00 mL of 0.10 mol L
-1 methylamine, CH
3NH
2, with 20.00 mL of 0.10 mol L
-1 methylammonium chloride, CH
3NH
3Cl? Assume that the volume of the solutions are additive and that
Kb = 3.70 × 10
-4 for methylamine.
◦ 10.97
◦ 10.17
◦ 10.57
◦ 11.78
Question 2
What is the pH of a buffer system prepared by dissolving 10.70 grams of NH
4Cl and 25.00 mL of 12 mol L
-1 NH
3 in enough water to make 1.000 L of solution?
Kb = 1.80 × 10
-5 for NH
3.
◦ 9.43
◦ 9.08
◦ 9.26
◦ 11.32