Question

At s.t.p 4g of hydrogen gas occupies how much volume?

Answer 1

4g hydrogen gas contains 2 moles of H₂.
Volume of 1 mole of a gas at STP = 22.4l
Volume = 2×22.4 = 44.8 l

Answer 2

2g H₂ at S.T.P.  = 22.4 L
4g H₂ at S.T.P.  = 22.4 x 2 L = 44.8 L