MCQ
$pH$  of $ 0.1\, M$  solution of a weak acid $ (HA) $ is $4.50. $ It is neutralised with $NaOH$ solution to decrease the acid content to half $pH$  of the resulting solution
  • A
    $4.50$
  • $8$
  • C
    $7$
  • D
    $10$

Answer

Correct option: B.
$8$
(b )$pH = pK_a + \log \frac{{[Salt]}}{{[Acid]}}$

$pH = pK_a$

$K_a = 0.1 \times {({10^{ - 3.5}})^2} = 0.1 \times {10^{ - 7}} = {10^{ - 8}}$ $⇒$ $pH = 8$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free