# What is the pH of a .025 M HCl solution?

Jun 6, 2016

The pH is 1.60.

#### Explanation:

Hydrochloric acid is a strong acid that completely dissociates in water.

For a 0.025 M HCl solution the concentration of the hydrogen ions, $\left[{\text{H}}^{+}\right]$, is 0.025 moles/liter (i.e. 0.025 M).

pH is defined as $- \log \left[{\text{H}}^{+}\right]$.

Substituting 0.025 into the equation for pH we find that the 0.025 M HCl solution has a pH of -log(0.025) = 1.60.