Question

At ${60}^{o}C$, pure water has $\left[H_3{O}^{+}\right]={10}^{-6.7}mol/lit$.What is the value of $K_W$ at ${60}^{o}C$ :-

• A. ${10}^{-6}$
• B. ${10}^{-12}$
• C. ${10}^{-67}$
• D. ${10}^{-13.4}$

Answer 1

The correct option is D ${10}^{-13.4}$

In pure water, $\left[H_3{O}^{+}\right]=\left[O{H}^{-}\right]$

$K_w=\left[H_3{O}^{+}\right]\left[O{H}^{-}\right]$

As given, $\left[H_3{O}^{+}\right]={10}^{-6.7}mol/lit$

So, $K_w={10}^{-6.7}\times {10}^{-6.7}={10}^{-13.4}$