Question

$pH$ of a solution is $5.0$ Its hydrogen ion concentration is decreased by $100$ times. The solution will then be:

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

Answer 1

The correct option is A neutral

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

Thus $\left[H^{+}\right]={10}^{-5}$.

The hydrogen ion concentration is decreased by 100 times.
Thus $\left[H^{+}\right]={10}^{-7}$.

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

Hence, the solution will be neutral.

Option A is correct.