What is the atomic mass of a gas that has rho=2.50*g*L^-1 at a pressure of 0.974*atm, and a temperature of 371*K?

1 Answer
Jan 24, 2017

Given PV=nRT.........."molar mass" ~= 80*g*mol^-1

Explanation:

P/(RT)=n/V=("mass"/"molar mass")/V

And thus "molar mass"="mass of gas"/(PV)xxRT

All I have done is manipulate the equation,

So "molar mass"="mass"/(V)xx(RT)/P

But "mass"/V="density", rho

Finally, "molar mass"=rhoxx(RT)/P

(2.50*g*cancel(L^-1)xx0.0821*cancel(L)*cancel(atm)*cancel(K^-1)*mol^-1xx371*cancel(K))/(0.974*cancel(atm))

=??*g*mol^-1