Question

If the density of a gas at the sea level at `0^(@)C` is `1.29 kg m^(-3)`, what is its molar mass? (Assume that pressure is equal to `1"bar"`.)

Answer 1

`pV_(m)=RT` or `pM//d=RT`
or `M=dRT//p`
`=(1.29kgm^(-3)xx8.314 N mK^(-1)mol^(-1)xx273.15 K)/(1.0xx10^(5) N m^(-2)(or Pa))`
`=(1.29xx8.314xx273.15 kg mol^(-1))/(1xx10^(5))`
`0.0293 kg mol^(-1)` or molar mass is `29.3 g mol^(-1)`