Question

The pH of a solution is $5$. If its $H^{+}$ ion concentration is decreased by $100$ times, then the nature of the solution formed is:

• A. acidic
• B. basic
• C. neutral
• D. amphoteric

Answer 1

The correct option is C neutral

Given that a solution has $pH=5$

$pH=-log\left[H^{+}\right]=5$

Hence, $\left[H^{+}\right]={10}^{-5}$

When hydrogen ion concentration is decreased by $100$ times, then
$\left[H^{+}\right]={10}^{-7}$

$pH=-log\left[H^{+}\right]=-log\left({10}^{-7}\right)=7$

This indicates a neutral solution.

Hence, the nature of the resulting solution is neutral.