Question

Which of the following solutions has pH equal to $10$?

• A. ${10}^{-4}M$ $KOH$
• B. ${10}^{-10}M$ $KOH$
• C. ${10}^{-10}M$ $HCl$
• D. ${10}^{-4}M$ $HCl$

Answer 1

The correct option is A ${10}^{-4}M$ $KOH$

$pH=10$ means $\left[H^{+}\right]={10}^{-10}M$

As we know that $\left[H^{+}\right]\left[O{H}^{-}\right]={10}^{-14}$

$\left[O{H}^{-}\right]={10}^{-4}$

So ${10}^{-4}M$ $KOH$ has $pH$ equal to 10.