$0.48 \ g$ of an organic compound on complete combustion produced $0.22 \ g$ of $CO_2$. The percentage of $C$ in the given organic compound is

Chlorophyll,the green pigment in plants responsible for photosynthesis,contains $2.68\%$ of magnesium by mass. Calculate the number of magnesium atoms in $2.00 \ g$ of chlorophyll.

By combustion of $0.2475 \ g$ of an organic compound,$0.4950 \ g$ of $CO_2$ and $0.2025 \ g$ of $H_2O$ are obtained. Calculate the percentage of $C, H,$ and $O$. Given atomic masses: $C = 12, H = 1, O = 16$.

Quantitative analysis of an organic compound $(X)$ shows the following percentage composition: $C: 14.5\%$,$Cl: 64.46\%$,and $H: 1.8\%$. The empirical formula mass of the compound $(X)$ is $.......... \times 10^{-1}$. (Given molar mass in $g \ mol^{-1}$ of $C: 12, H: 1, O: 16, Cl: 35.5$)

On complete combustion,$1.4 \, g$ of a hydrocarbon gave $1.8 \, g$ of water. The empirical formula of the hydrocarbon is:

When $0.01 \ mol$ of an organic compound containing $60 \%$ carbon was burnt completely,$4.4 \ g$ of $CO_2$ was produced. The molar mass of the compound is $......... \ g \ mol^{-1}$ (Nearest integer).