Question

A gas sample contains 4.00 g of ch4 and 2.00 g of he. what is the volume of the sample at stp? 5.64 l 32.0 l 22.4 l 16.8 l 132 l

Answer 1

The gas sample consists of CH₄ and He.
Number of CH₄ moles - 4 g/ 16 g/mol = 0.25 mol
molar volume is where 1 mol of any gas occupies a volume of 22.4 L 
Therefore 0.25 mol of CH₄ gas occupies a volume of 22.4 L/mol x 0.25 mol
Volume of methane - 5.6 L 
Number of He moles - 2.00 g/ 4 g/mol = 0.5 mol 
Volume occupied by He - 22.4 L /mol x 0.5 mol = 11.2 L
The total volume of the sample = 5.6 L + 11.2 L = 16.8 L