Question

Volume of 10 g of a gas is 5.6 litre at NTP. What will be the molecular weight of that gas

Answer 1

1-1mol of gas at STP occupies 22.4 L

So 5.6 L has 0.25 mol of gas

2- molar mass of gas = sample mass ÷ number of moles

So Mwt = 10÷0.25= 40g/mol

Answer 2

Volume of the gas = 5.6 L

Mass of the gas = 10g

Molecular weight = ?

At ntp the temperature is 293.15 K( 20 degree Celsius)

And the pressure is 1 atm

the volume at ntp is 24.05 L.

Molecular weight is

= (given mass/ given volume )*volume at NTP.

Here comes your answer,

=(10/5.6) * 24.05

=42.95g