Question

An organic compound contains $69\%$ carbon and $4.85$ hydrogen, the remainder being oxygen. The masses of carbon dioxide and water produced when $0.20$ g of this substance is subjected to complete combustion?

• A. $0.506$g and $0.0864$ g
• B. $0.678$g and $0.0234$ g
• C. $0.786$g and $0.0128$ g
• D. None

Answer 1

The correct option is A $0.506$g and $0.0864$ g

Percentage of carbon in organic compound is $69\%$

Hence,

$0.20$ gram of organic compound $=0.69\times 0.20=0.138$ gram of water

Therefore,

Now it produced $C{O}_2$

$12$ gram of carbon produces $44$ gram of $C{O}_2$

Hence,

$0.138$ gram of carbon produces $=\frac{44\times 0.138}{2^2}=0.506$ gram of $C{O}_2$

Similarly,

For hydrogen

$4.8\%$ of hydrogen in $0.20$ gram of organic compound.

We have $0.0096$ gram of hydrogen.

Hence ,

For $H_{2}O$

$18$ gram of water --$2$ gram of hydrogen

Therefore, $0.0096$ gram will produce $=18\times 0.0092=0.0864$ gram of water.