Question

Which of the statements below about an acid-base buffer solution is/are true?
I. It can be prepared by combining a strong acid with a salt of its conjugate base.
II. It can be prepared by combining a weak acid with a salt of its conjugate base.
III. It can be prepared by combining a weak base with its conjugate acid.
IV. The pH of a buffer solution does not change when the solution is diluted.
V. A buffer solution resists changes in its pH when an acid or base is added to it.
A. I, II, and IV.
B. II, III, and V.
C. II, III, IV, and V.
D. I, II, IV, and V.
E. II, III, and IV.

Answer 1

Answer:

C. II, III, IV, and V.

Explanation:

Acid buffer is  generally formed by the combination of a weak acid as well as the salt of the conjugate base.

Basic buffer is formed the combination of a weak base and also the salt of the conjugate acid.

On dilution the ration of the concentration terms of the salt and weak acid/base does not change. Hence the pH of the buffer solution does not change.

When acid or base is added to buffer, it resists changes in the pH.

Therefore, option (C) is correct.