the density of a gas at N.T.P is 1.40grams per litre. The molecular weight of gas is

Answer 1

PV=nRT

n/V=P /RT n/V; but n=mass/molmass*volume, so density/molmass=n/V

n/V=density/molmass then
molmass=density*RT/Pressure

put in NTP, and you have it.

Answer 2

Answer

Answer 3

31.36