Question

Calculate $pH$ of the (write the value to the nearest integer) ${10}^{-8}M$ $HCl$.

• A. $6.95$
• B. 7.9
• C. 5.9
• D. 6

Answer 1

The correct option is A $6.95$

We have

$pH=-log\left(H^{+}\right)$

$HCl\to H^{+}\left({10}^{-8}\right)+C{l}^{-}$

and $H_{2}O\to H^{(}{10}^{-7})++O{H}^{-}$

so, $pH=-log({10}^{-8}+{10}^{-7})$

so, pH = 6.95