The density of a gas under given conditions of temperature and pressure is calculated by dividing its mass density by that of air: $d_{gaz}=\frac{\rho_{gaz}}{\rho_{air}}$ Knowing that ntp ($0\;^oC$ et $1\;atm$) the mass density of air is: $\rho_{air}=1.292\frac{g}{L}$, calculate the density of methane $CH_4 $ ntp! Solution (Click): Let's take one mole of methane, $ 16.0 \; g $ and calculate its volume ntp:: Ideal gas law: .......... Calculation: .......... Answer: ..........