Molecular Weight of Air?

Question

Given air is 78.08 mol% N2, 20.95 mol% O2, 0.93 mol% Ar and 0.04 mol% CO2, calculate the average

molecular weight of dry air in units of g/mol. Use the appropriate number of significant figures.

Answer 1

You can have Mol.Wt of one element.Air is composed of many elements like different gases.