Question

What is the $pH$ of $1M$ $HCl$?

• A. $0$
• B. $1$
• C. $2$
• D. $3$

Answer 1

The correct option is A $0$

$HCl$ is a strong electrolyte, hence it dissociates completely.

$HCl\to H^{+}+C{l}^{-}$

Thus,

$\left[HCl\right]=\left[H^{+}\right]=1M$

$\therefore pH=-{\log }_{10}\left[H^{+}\right]=-lo{g}_{10}1=-{\log }_{10}{10}^o=0$

$\therefore pH=0$

Hence, option $A$ is correct.