MCQ
Number of $gm$ of oxygen in $32.2\,g$ $N{a_2}S{O_4}.10{H_2}O$ is
  • A
    $20.8$
  • $22.4$
  • C
    $2.24$
  • D
    $2.08$

Answer

Correct option: B.
$22.4$
b
(b) $N{a_2}S{O_4}\;.\;10{H_2}O$ $ = 2 \times 23 + 32 + 4 \times 16 + 10 \times 18$ $= 46 + 32 + 64 + 180 = 322\,gm$

$322\,gm$ $N{a_2}S{O_4}.10{H_2}O$ contains = $224 \,gm$ oxygen

$32.2\,gm$ $N{a_2}S{O_4}.10{H_2}O$ contains = $\frac{{32.2 \times 224}}{{322}} = 22.4\,gm$

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