Question

Determine the $pH$ of a solution that is 0.03 M $HCl$.

• A. 4.88
• B. 2.88
• C. 4.52
• D. 1.52

Answer 1

The correct option is D 1.52

Since $HCl$ is a strong acid, it will dissociate completely into it's ions at equilibrium.
The dissociation of HCl in aqueous medium is given by :$HCl\stackrel{+H_{2}O}{⟶}{H}_3{O}^{+}+C{l}^{-}Initial:C00Equilibrium:0CC$.
$[HCl{]}_{initially}=C=0.03M[H_3{O}^{+}{]}_{eqb.}=C=0.03$

$pH=-{\log }_{10}\left[H_3{O}^{+}\right]$
$pH=-{\log }_{10}\left(0.03\right)=2-lo{g}_{10}\left(3\right)=2-0.48pH=1.52$