Question

0.1 M H Cl solution is diluted by 100 times. The pH of the solution so formed is:

• A. 1
• B. 2
• C. 3
• D. 4

Answer 1

The correct option is C 3

When 0.1 M HCl solution is diluted 100 times, its concentration becomes 0.001 M.
HCl being a strong electrolyte completely dissociates. Thus, $\left[HCl\right]=\left[H^{+}\right]=0.001$ M.
$pH=-log\left[H^{+}\right]=-log0.001=3.0$.