Complete combustion of

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Question:

Complete combustion of $1.80 \mathrm{~g}$ of an oxygen containing compound $\left(\mathrm{C}_{\mathrm{x}} \mathrm{H}_{\mathrm{y}} \mathrm{O}_{\mathrm{z}}\right)$ gave $2.64 \mathrm{~g}$ of $\mathrm{CO}_{2}$ and $1.08 \mathrm{~g}$ of $\mathrm{H}_{2} \mathrm{O}$. The percentage of oxygen in the organic compound is:

  1. 51.63

  2. 63.53

  3. 53.33

  4. 50.33


Correct Option: , 3

Solution:

$\mathrm{n}_{\mathrm{c}}=\mathrm{n}_{\mathrm{co}_{2}}=\frac{2.64}{44}=0.06$

$\mathrm{n}_{\mathrm{H}}=2 \times \mathrm{n}_{\mathrm{H}_{2} \mathrm{O}}=\frac{1.08}{18} \times 2=0.12$

$\mathrm{m}_{0}=1.80-12 \times \frac{2.64}{44}-\frac{1.08}{18} \times 2$

$=1.80-0.72-0.12=0.96 \mathrm{gm}$

$\% 0=\frac{0.96}{1.80} \times 100=53.33 \%$

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