Which of the following mixtures will act as a buffer solution when dissolved in 50 mL of water ?

Options

A. 0.2 mol of aniline `+0.2` mol HCl
B. 0.2 mol of aniline `+0.4` mol of NaOH
C. 0.2 mol of NaCl `+0.1` mol of HCl
D. 0.2 mol aniline
+
0.1 mol of HCl

Answer

D

Explanation

Aniline and its salt with HCl will act as a buffer solution
0.2 mol aniline `+` 0.1 mol of HCl
`=` 0.1 mol of aniline hydrochloride `+` 0.1 mol aniline