General Chemistry 1

Question

The Ostwald process is used commercially to produce nitric acid, which is, in turn, used in many modern chemical processes. In the first step of the Ostwald process, ammonia is reacted with oxygen gas to produce nitric oxide and water.

What is the maximum mass of H2O that can be produced by combining 82.1g of each reactant?

4NH3(g)+5O2(g)⟶4NO(g)+6H2O(g)

Answer 1

Use stoichiometry of the balanced equation and dimensional analysis.

82.1 g NH₃ x 1 mol NH₃ / 17 g x 6 mol H₂O/4 mol NH₃ x 18 g H₂O/mol = 130 g H₂O from 82.1 g NH₃

82.1 g O₂ x 1 mol O₂ / 32 g x 6 mol H₂O/5 mol O₂ x 18 g H₂O/mol = 55.4 g H₂O from 83.1 g O₂

So, O₂ would be the limiting reactant and thus the maximum mass of H₂O than can be produced is 55.4 g