Question

What will be the pH of a buffer solution containing an acid of pKa7.5, with an acid concentration exactly one fourth of that of the conjugate base

Answer 1

Answer: pH of buffer solution is 8.1

Explanation:

The formula for the Henderson–Hasselbalch equation is:

$pH=pK_a+\log\frac{[A^-]}{[HA]}$

$pH$ is the concentration of $[H^+]$

$pK_a$ is the acid dissociation constant,

$A^-$ and $HA$ are concentrations of the conjugate base and starting acid.

Putting in the values we get:

$pH=7.5+\log\frac{x}{\frac{x}{4}}$

$pH=8.1$

Thus pH of buffer solution is 8.1