If we want to study the relative arrangement of atoms in a molecule,we study:

The empirical formula of Calgon is

On reduction with hydrogen,$3.6 \ g$ of an oxide of metal $(M)$ left $3.2 \ g$ of the metal. If the atomic weight of the metal is $64$,the formula of the oxide is:

Among the following,the compound with the highest percentage of chlorine is:

$A$ sample of calcium carbonate $(CaCO_3)$ has the following percentage composition: $Ca = 40\%$; $C = 12\%$; $O = 48\%$. If the law of constant proportions is true,then the weight of calcium in $4 \, g$ of a sample of calcium carbonate obtained from another source will be $... \, g$.

What is the mass of oxygen in $32.2 \ g$ of $Na_2SO_4 \cdot 10H_2O$ (in $g$)?