Question

$pH$ of pure $H_{2}O$ at ${25}^{\circ }C$ is:

• A. $>7$
• B. $<7$
• C. 7
• D. 14

Answer 1

The correct option is C 7

$K_{w}at{25}^{0}C\to {10}^{-14}$

$K_w=\left[H^{+}\right]\left[O{H}^{-}\right]$

$H^{+}={10}^{-7}$

$\therefore P^H=-log\left[H^{+}\right]$

$=-log(10{)}^{-7}$

$p^H=7$

Option C is correct.