A student collects a sample of gas and finds that 1.01 g of the gas will fill a container with a volume of 0.225 L at STP. What is the molar mass of the gas?

1 Answer
Jan 23, 2016

#MM=101g/(mol)#

Explanation:

At STP, we know that the molar volume of a gas is #22.42L/(mol)#, therefore, now we can calculate the number of mole of the gas from its volume #V=0.225L# at STP.

#=>n=0.225cancel(L)xx(1mol)/(22.42cancel(L))=0.01 mol#

From the number of mole and the mass of the sample (#m=1.01g#) we can find the molar mass of the gas:

#n=m/(MM)=>MM=m/n=(1.01g)/(0.01mol)=101g/(mol)#