What mass of ammonia could we make from 100.0 grams each of N2 and H2?

Question

What mass of ammonia could we make from 100.0 grams each of N2 and H2?

Answer 1

First write a balanced equation for the reaction. 

N2 + 3H2 ==>2NH3

Next, find the limiting reactant 

Moles N2 = 100g x 1 mol/28g = 3.57 mol N2

Moles H2 = 100 g x 1 mol/2 g = 50 moles H2

Limiting reactant is N2

Mass NH3 formed = 3.57 mol N2 x 2 mol NH3/mol N2=7.14 moles NH3 x 17 g/mol = 121 g NH3