Question

Calculate the pH of 0.05m NaOH solution.

Answer 1

Since NaOH is base, firstly, We have to find pOH
$pOH=-log\left[0.05\right]$

$pOH=-log[5\times {10}^{-2}]$

$pOH=-[log5+2log10]$

$pOH=2-log5$ ( since log 10 =1)

$pOH=2-0.6990$

$pOH=1.301$

$pH+pOH=14$

$pH=14-1.301$

$pH=12.69$