Question

100ml of 0.1 M NaOH is added to 100 ml of a 0.2 M $C{H}_{3}COOH$ solution. The pH of resulting solution will be (pka=4.74) :

Answer 1

$NaOH+C{H}_{3}COOH⟶C{H}_{3}COONa+H_{2}O$

$10$ $m$ $mol$ $20$ $m$ $mol$

$0$ $10$ $m$ $mol$ $10$ $m$ $mol$

Now it is a buffer

$pH=p{k}_a+\log \left[\frac{salt}{acid}\right]$

$pH=4.74+\log 1=4.74$