Part 1: In a solution, when the concentrations of a weak acid and its conjugate

ID: 809895 • Letter: P

Question

Part 1: In a solution, when the concentrations of a weak acid and its conjugate base are equal, ________.

a. the buffering capacity is significantly decreased

b. the -log of the [H+] and the -log of the Ka are equal

c. All of these are true.

d. the system is not at equilibrium

Part 2:

Of the following solutions, which has the greatest buffering capacity?

Select one:

a. 0.234 M NH3 and 0.100 M NH4Cl

b. 0.543 M NH3 and 0.555 M NH4Cl

c. 0.100 M NH3 and 0.455 M NH4Cl

d. They are all buffer solutions and would all have the same capacity.

e. 0.087 M NH3 and 0.088 M NH4Cl

Part 3:

Which of the following could be added to a solution of acetic acid to prepare a buffer?

Select one:

a. sodium hydroxide only

b. hydrofluoric acid or nitric acid

c. sodium acetate only

d. sodium acetate or sodium hydroxide

e. nitric acid only

part A : answer b

part B : answer d

part C : answer a