What is the amount of ammonia (17.03 g/mol) that can be obtained by complete reaction of 35 g of nitrogen gas (28.01 g/mol) with excess hydrogen gas

Question

What is the amount of ammonia (17.03 g/mol) that can be obtained by complete reaction of 35 g of nitrogen gas (28.01 g/mol) with excess hydrogen gas

according to the balanced equation:

N2 + 3H2 = 2NH3

Answer 1

Look at the balanced equation:

3H₂ + N₂ ==> 2NH₃

35 g N₂ x 1 mol N₂/28.01 g = 1.2496 moles N₂

1.2496 moles N₂ x 2 moles NH₃/1 mole N₂ = 2.499 moles NH₃

mass NH₃ = 2.499 moles NH₃ x 17.03 g/mol = 42.55 g NH₃ = 43 g NH₃ (to 2 sig. figs. based on 35 g)