What mass of nitrogen gas is required to react completely with 2.79 g of hydrogen gas to produce ammonia?

The balanced equation for the formation of ammonia is as follows

N₂ + 3H₂ - - - > 2NH₃

stoichiometry of H₂ to N₂ is 3:1

number of H₂ moles reacted - 2.79 g / 2 g/mol = 1.40 mol

if 3 mol of H₂ reacts with 1 mol of N₂

then 1.40 mol of H₂ reacts with - 1.40/3 = 0.467 mol of N₂

mass of N₂ required - 0.467 mol x 28 g/mol = 13.1 g

mass of N₂ formed is 13.1 g