$A$ 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 $.3$)?

$A$ gaseous hydrocarbon gives upon combustion $0.72 \ g$ of water and $3.08 \ g$ of $CO_{2}$. The empirical formula of the hydrocarbon is:

An oxide of sulfur contains $50\%$ sulfur. What is its empirical formula?

$2.0 \text{ g}$ of a bromo hydrocarbon $(X)$ was subjected to Carius analysis,which gave $3.36 \text{ g}$ of $AgBr$. The percentage of carbon in the compound $(X)$ is $26.7\%$. The total number of carbon atoms in the empirical formula for compound $(X)$ is . . . . . . .

In the crystalline solid $MSO_{4} \cdot nH_{2}O$ of molar mass $250 \ g \ mol^{-1}$,the percentage of anhydrous salt is $64$ by weight. The value of $n$ is

$A$ metal oxide $M$ contains $40\%$ oxygen by mass. The atomic mass of metal $M$ is $24$. The empirical formula of the oxide is....