What is the relationship between the molecular mass,density,and volume of a gas?

(N/A) For a gas,the relationship between its molecular mass $(M)$,volume $(V)$,and density $(d)$ is given by the ideal gas equation $PV = nRT$.
Since $n = \frac{m}{M}$,where $m$ is the mass of the gas,we have $PV = \frac{m}{M}RT$.
Rearranging for density $(d = \frac{m}{V})$,we get $d = \frac{PM}{RT}$.
Thus,at constant temperature and pressure,the density of a gas is directly proportional to its molecular mass $(d \propto M)$.