Question

You have a 1 L container of a gas O 2 at 20°C and 1 atm. Subtracting the weight of the container, what is the mass of the gas?

Answer 1

PV=nRT *n = #mol*

n=PV/RT
(1atm*1L)/(0.0821(L*atm/K*mol)*293K)=n
0.42=n

1mol O2= 32g O2 (according to the periodic table)
0.42mol*32g = 13.44g O2