On complete combustion of $0.492 \mathrm{~g}$ of an organic compound containing $\mathrm{C}, \mathrm{H}$ and $\mathrm{O}$, $0.7938 \mathrm{~g}$ of $\mathrm{CO}_{2}$ and $0.4428 \mathrm{~g}$ of $\mathrm{H}_{2} \mathrm{O}$ was produced. The % composition of oxygen in the compound is ___________.
Answer (integer)
46
Solution
$\%$ of $\mathrm{H}=\frac{2}{18} \times \frac{\text { wt. of } \mathrm{H}_{2} \mathrm{O}}{\text { wt. of organic compound }} \times 100$
<br/><br/>
$$
\begin{aligned}
&=\frac{2}{18} \times \frac{0.4428}{0.492} \times 100 \\\\
&=0.11 \times 0.9 \times 100 \\\\
&=0.099 \times 100=9.9
\end{aligned}
$$
<br/><br/>
$\%$ of $C=\frac{12}{44} \times \frac{0.7938}{0.492} \times 100$
<br/><br/>
$$
\begin{aligned}
&=0.27 \times 1.61 \times 100 \\\\
&=43.47
\end{aligned}
$$
<br/><br/>
$\% \text { Oxygen }=100-(43.47 + 9.9)$
<br/><br/>
$=100-53.37 \simeq 46$
About this question
Subject: Chemistry · Chapter: Some Basic Concepts of Chemistry · Topic: Mole Concept
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