Question

Consider the reaction between $\mathit{N}\mathit{O}\mathbf{\left(}\mathit{g}\mathbf{\right)}$and ${\mathit{O}}_{\mathbf{2}}\mathbf{\left(}\mathit{g}\mathbf{\right)}$represented below.

What is the balanced equation for this reaction and what is the limiting reactant?

Short answer

The balanced equation for this reaction is:

$2NO+O_2\to 2N{O}_2$

and its limiting reactant is $\text{NO}$

Step-by-step solution

Definition

A balanced chemical equation is one in which the number of atoms present on the reactant side of the equation equals the number of atoms present on the product side of the equation.

Depict molecules involved in the reaction

Write down the molecules involved in the chemical reaction (excluding unreacted molecules).

$NO+O_2\to N{O}_2$

According to the diagram above, there are four molecules of NO and four ${\text{O}}_2$ molecules. But for every two molecules of NO, one molecule of oxygen is required.

$2NO+O_2\to 2N{O}_2$

Limiting reagent

For four molecules of oxygen, eight molecules of NO are required. But only four are provided.

$\text{NO}$is the limiting reactant because there are still oxygen molecules in the reactant but not enough $\text{NO}$molecules to generate the required product.