Question

An organic compound contains 69% carbon and 4.8% hydrogen, the remainder being oxygen. What will be the masses of the carbon dioxide and water produces when 0.20g of this substance is subjected to the complete combustion?

• A. 0.69 g and 0.048g
• B. 0.506 g and 0.086g
• C. 0.345 g and 0.0024 g
• D. 0.91 g and 0.72 g

Answer 1

Answer: (B)

0.506 g and 0.086g

Given :

% of $C=69\%$, % of $H=4.8\%$

$44g$ of $C{O}_2$ has $12g$ of C

$1g$ of $C{O}_2=\frac{12}{44}g$ of C

$\%C=\frac{12}{44}\times \frac{w_c}{0.2}\times 100$

$\frac{44\times 69\times 0.2}{12\times 100}=w_c$

$w_c=0.506$

$18g$ of $H_{2}O$ has $2g$ of H

$1g$ of $H_{2}O=\frac{2}{18}gH$

$w_{H_2}O$ of $H_{2}O$ has $\frac{2}{18}\times w_{H_{2}O}$

$\%$ of $H=\frac{2}{18}\times \frac{w_{H_{2}O}}{0.2}\times 100$

$4.8=\frac{2}{18}\times \frac{w_{H_{2}O}}{0.2}\times 100$

$w_{H_{2}O}=0.0864g$

Weight of Carbon and Hydrogen in the organic compound are $0.506g$ and $0.0864g$, respectively.