The density of a gas is `0.259 gL^(-1)` at 400 K and 190 torr. Find its molar mass:

Explanation

760 torr = 1 atm
So 190 torr `= (190)/(760) atm`
We know that, `P = (d)/(M) RT`
or `M = (d)/(P) RT`
Given, `d = 0.259 g L^(-1), " " P = (190)/(760) atm`,
`R = 0.0821 L - atm K^(-1) mol^(-1), " " T = 400 K`
`M = (0.259 xx 0.0821 xx 400 xx 760)/(190) = 34.02 g mol^(-1)`