An organic compound gives 0.220 g of $\mathrm{CO}_{2}$ and 0.126 g of $\mathrm{H}_{2} \mathrm{O}$ on complete combustion. If the % of carbon is 24 then the % hydrogen is ______ $\times 10^{-1}$. (Nearest integer)

JEE Main · 2023 · 13 Apr 2023 · Shift 1 · Some Basic Concepts of Chemistry

An organic compound gives 0.220 g of

CO_{2}

and 0.126 g of

H_{2} O

on complete combustion. If the % of carbon is 24 then the % hydrogen is ______

\times 1 0^{- 1}

. (Nearest integer)

Answer: 56

Moles of

CO_{2} = \frac{0.220}{44} = \frac{1}{200}

, so moles of C

= \frac{1}{200}

and mass of C

= \frac{1}{200} \times 12 = 0.06

g. Given % of C

= 24 = \frac{0.06}{W} \times 100

, so

W = 0.25

g (mass of compound). Moles of

H_{2} O = \frac{0.126}{18} = 0.007

, so moles of H

= 2 \times 0.007 = 0.014

and mass of H

= 0.014

g. % of H

= \frac{0.014}{0.25} \times 100 = 5.6 = 56 \times 1 0^{- 1}

JEE Main · 2023 · 13 Apr 2023 · Shift 1 · Integer answer