A molar volume of gas has a density of #1.7824*g*L^-1# at #"STP"#. What is the molecular mass of this gas?

2 Answers
Jul 7, 2017

Answer:

Well the molar volume of an Ideal Gas at #STP# is #22.4*L#

Explanation:

We assume Ideal Gas behaviour..........

And thus, at #STP#, we have gots a molar mass of........

#22.414*L*mol^-1xx1.7824*g*L^-1=39.95*g*mol^-1#......

You should be able to identify this gas #"pdq"#.

Jul 7, 2017

we know , 22.4 L of any gas gas at STP is 1 mol of the gas.

We have been given that the density of an elemental gas is 1.7824g/L at STP.

Hence mass of 22.4 L of the elemental gas gas at STP is its molar mass.
Hence molar mass #=22.4L/"mol"xx1.7824g/L~~39.9258g"/"mol#