For this solution one would use the variation of the Ideal Gas Law PM = dRTPM=dRT P = PressureP=Pressure in atmatm M = Molar MassM=MolarMass in g/(mol)gmol d = Densityd=Density in g/LgL R = 0.0821 (atmL)/(molK)R=0.0821atmLmolK the gas law constant T = TemperatureT=TemperatureKK
The density can be found by dividing the mass by the volume.
d = (mass)/(volume) = g/Ld=massvolume=gL
mass = 40.0 gmass=40.0g volume = 11.2 Lvolume=11.2L
d = (40.0g)/(11.2 L)d=40.0g11.2L d = 3.57 g/Ld=3.57gL
The STP values (standard temperature and pressure) are 1 atm and 273 K.
P = 1 atmP=1atm M = ?M=? d = 3.57 g/Ld=3.57gL R = 0.0821 (atmL)/(molK)R=0.0821atmLmolK T = 273KT=273K