Question

Stoichiometry #2 At Home Practice • Show all work using the factor label method • Use units and label chemical formulas for all conversion factors • Report final answer with the correct number of significant figures, unit and chemical formula Limiting Reactant Calculations 2 NO(g) + 5 H2(g) → 2 NH3(g) + 2 H2O(g) Starting with 75.4 g NO and 15.5 g Hz, what is the theoretical yield of NH3 in grams? Calculation based upon NO Calculation based upon H2 What is the limiting reactant? What is the theoretical yield?

Answer 1

1) moles of NO = 75.4 gm / 30.01 gm mol--1 = 2.512 mol

Moles of H2 = 15.5 gm / 2 gm mol--1 = 7.75 mol

So according to reaction stochimetry

a)moles of NO = (2moles of NH3 / 2 moles of NO) x 2.512 mol NO

Theoretical yield of NH3 = 2.512 mol NH3 x (17 gm NH3/ 1 mol NH3)

= 42.7 gm NH3

b) moles of NH3 = (2 mol NH3 / 5 mol H2) x 7.75 mol H2

= 3.1 mol NH3

Theoretical yield of NH3 = 3.1 mol x 17 gm mol--1

= 52.7 gm NH3

c) since NO produces least amount of ammonia it is limiting reagent.

d ) so according to calculation of NO ( limiting reagent ) theoretical yield is 42.7 gm NH3