Question

The chemical equation represents a reaction between ammonia and oxygen to form nitrogen monoxide and water. 4 N H 3 ( g ) + 5 O 2 ( g ) → 4 NO ( g ) + 6 H 2 O ( g ) What is the limiting reagent when a 4.50 g sample of ammonia is mixed with 15.80 g of oxygen?

Answer 1

The limiting reagent : NH₃

Further explanation

A method that can be used to find limiting reactants is to divide the number of moles of known substances by their respective coefficients, and small or exhausted reactants become a limiting reactant

Reaction

4NH₃(g)+5O₂(g)⇒4NO(g)+6H₂O(g)

mol NH₃ :

$\tt \dfrac{4.5}{17}=0.265$

mol O₂ :

$\tt \dfrac{15.8}{32}=0.494$

mol ratio

NH₃ :

$\tt \dfrac{0.265}{4}=0.06625$

O₂ :

$\tt \dfrac{0.494}{5}=0.0988$

Limiting reactants : NH₃ (smaller ratio)