The formula which represents the simplest ratio of atoms of different elements present in a molecule of a substance is called:

$2.0 \text{ g}$ 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 . . . . . . .

The chemical formula for calcium pyrophosphate is $Ca_2P_2O_7$. What is the formula for ferric pyrophosphate?

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

$0.5 \ g$ of an organic compound $(X)$ with $60 \%$ carbon will produce $........ \times 10^{-1} \ g$ of $CO_2$ on complete combustion.

In an organic compound,the percentage of $C$ is $92.3 \%$. What is its empirical formula?