The empirical formula of a hydrocarbon containing $80\%$ carbon and $20\%$ hydrogen is:

An organic compound is estimated through the Dumas method and is found to evolve $6$ moles of $CO_2$,$4$ moles of $H_2O$,and $1$ mole of nitrogen gas. The formula of the compound is

Reduction of $7.2 \, g$ of a metal oxide yields $6.4 \, g$ of the metal. If the atomic mass of the metal is $128 \, g/mol$,the formula of the oxide is .....

$120 \ g$ of an organic compound that contains only carbon and hydrogen gives $330 \ g$ of $CO_{2}$ and $270 \ g$ of water on complete combustion. The percentage of carbon and hydrogen,respectively,are ...... .

The empirical formula of glucose is...

$A$ metal $M$ sulfate contains $9.87 \% \, M$. If it is isomorphous with $ZnSO_4 \cdot 7H_2O$,what is the atomic mass of $M$ (in $.3$)?