Question

The ionic product of water is ${10}^{-14}$, What is the $H^{+}$ ion concentration of a 0.1 M Na OH solution?

• A. ${10}^{-14}M$
• B. 14M
• C. 13M
• D. ${10}^{-13}M$

Answer 1

Answer: (D)

${10}^{-13}M$

NaOH is a strong electrolyte and completely dissociates in solution.
Hence, $\left[O{H}^{-}\right]=0.1$.
The ionic product of water is ${10}^{-14}$.
Hence, $k_w=\left[H^{+}\right]\left[O{H}^{-}\right]={10}^{-14}$ or $\left[H^{+}\right]=\frac{{10}^{-14}}{\left[O{H}^{-}\right]}=\frac{{10}^{-14}}{0.1}={10}^{-13}$.