Question

A solution is made by adding $5.6$g of $KOH$ (molar mass $56\frac{g}{mol}$) to enough water to make $1.0$L of solution. What is the approximate pH of the resulting solution?

• A. $1$
• B. $3$
• C. $7$
• D. $9$
• E. $13$

Answer 1

The correct option is E $13$

$\left[KOH\right]=\frac{5.6}{56}=0.1M=\left[O{H}^{-}\right]$
$pOH=-log\left[O{H}^{-}\right]=-log0.1=1$
$pH=14-pOH=14-1=13$