MCQ
A weak acid is $ 0.1\% $ ionised in $0.1\, M $ solution. Its $pH$  is
  • A
    $2$
  • B
    $3$
  • $4$
  • D
    $1$

Answer

Correct option: C.
$4$
(c) For a monobasic acid

$[{H^ + }] = C\alpha $

$ = \frac{1}{{10}} \times 0.001 = {10^{ - 4}}$ $⇒ pH = 4$

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