The balanced equation for the formation of ammonia is as follows N₂ + 3H₂ ---> 2NH₃ stoichiometry of N₂ to H₂ is 1:3 we need to find the moles of N₂, volume of N₂ has been given molar volume is where 1 mol of any gas occupies a volume of 22.4 L at STP. if 22.4 L is occupied by 1 mol then 3.5 L of gas is occupied by - 3.5 L / 22.4 L/mol = 0.16 mol number of moles of N₂ present - 0.16 mol 1 mol of N₂ requires 3 mol of H₂ therefore 0.16 mol of N₂ requires - 3 x 0.16 = 0.48 mol of H₂ mass of H₂ required - 0.48 mol x 2 g/mol = 0.96 g 0.96 g of H₂ is required
