Question

4.4 gram unknown gas take 2.24 litres of volume, what is the gas name

Answer 1

At STP 22.4L of any gas (assuming its ideal nature)≡ 1g-molecular 

i.e. 1mole of that gas

Here,
2.24 L of volume at STP ≡ 4.4g
∴ 22.4L  of volume at STP ≡ 44g

So, molecular mass of the gas is 44g/mol
The gas may be CO2, C3H8(Propane)