Question:
$1.86 \mathrm{~g}$ of aniline completely reacts to form acetanilide. $10 \%$ of the product is lost during purificatiion. Amount of acetanilide obtained after purification (in g) is _____________$\times 10^{-2}$
Solution:
(243)
Molar mass $=93$ Molar mass $=135$
$93 \mathrm{~g}$ Aniline produce $135 \mathrm{~g}$ acetanilide
$1.86 \mathrm{~g}$ produce $\frac{135 \times 1.86}{93}=2.70 \mathrm{~g}$
At $10 \%$ loss, $90 \%$ product will be formed after purification.
Amount of product obtained $=\frac{2.70 \times 90}{100}=2.43 \mathrm{~g}=243 \times 10^{-2} \mathrm{~g}$