Question

calculate the volume occupied by(i) 28u nitrogen gas (ii) 28g N2 gas at STP.

Answer 1

. 28 u represents the molecular mass of N2gas.
Now, 1 mole of a gas contains 6.022 x 1023molecules.

Volume occupied by 1 mole(6.022 x 1023  molecules) of N2 gas at STP = 22.4 L
  Volume occupied by 1 molecule of N2 gas at STP = 22.4 L/6.022 x1023
  = 3.72 x 10-23 L

2. 28 g represent molar mass of N2 gas
Now,
Volume occupied by 1 mole of N2 gas at STP = 22.4 L