question_answer 1)

On complete combustion, 0.246 g of an organic compound gave 0.198 g of carbon dioxide and 0.1014 g of water. Determine the percentage composition of carbon and hydrogen in the compound.

Answer:

Percentage of carbon = \[\frac{12}{44}\times \frac{mass\,of\,C{{O}_{2}}}{mass\,of\,compound}\times 100\] \[=\frac{12\times 0.918\times 100}{44\times 0.246}=21.95%\] Percentage of hydrogen = \[\frac{2}{18}\times \frac{mass\,of\,{{H}_{2}}O}{mass\,of\,compound}\times 100\] \[=\frac{2\times 0.1014\times 100}{18\times 0.246}=4.58%\] Composition of the compound: C = 21.95%; H = 4.58%; O = 73.47%