Chapter 12, Problem 82A

(a)

Interpretation Introduction

Interpretation: Each of the equations is to be balanced.

Concept Introduction: Reactants, products, and an arrow indicating the reaction's direction make up a chemical equation. A balanced chemical equation is one in which the number of atoms in each of the molecules is the same on both sides of the equation.

Answer to Problem 82A

The balanced chemical equation is as follows:

  $\begin{array}{l}{\text{4NH}}_{\text{3}}{\text{+5O}}_{\text{2}}\to 4{\text{NO+6H}}_{\text{2}}\text{O}\hfill \\ {\text{2NO+O}}_{\text{2}}\to 2{\text{NO}}_{\text{2}}\hfill \\ {\text{3NO}}_{\text{2}}{\text{+H}}_{\text{2}}\text{O }\to 2{\text{HNO}}_{\text{3}}\text{+NO}\hfill \end{array}$

Explanation of Solution

The nitric acid is produced in three steps.

  $\begin{array}{l}{\text{NH}}_{\text{3}}{\text{+O}}_{\text{2}}\to {\text{NO+H}}_{\text{2}}\text{O}\hfill \\ {\text{NO+O}}_{\text{2}}\to {\text{NO}}_{\text{2}}\hfill \\ {\text{NO}}_{\text{2}}{\text{+H}}_{\text{2}}\text{O }\to {\text{HNO}}_{\text{3}}\text{+NO}\hfill \end{array}$

The balanced chemical equation is as follows:

  $\begin{array}{l}{\text{4NH}}_{\text{3}}{\text{+5O}}_{\text{2}}\to 4{\text{NO+6H}}_{\text{2}}\text{O}\hfill \\ {\text{2NO+O}}_{\text{2}}\to 2{\text{NO}}_{\text{2}}\hfill \\ {\text{3NO}}_{\text{2}}{\text{+H}}_{\text{2}}\text{O }\to 2{\text{HNO}}_{\text{3}}\text{+NO}\hfill \end{array}$

(b)

Interpretation Introduction

Interpretation: The mass of nitric acid is to be calculated.

Concept Introduction: Reactants, products, and an arrow indicating the reaction's direction make up a chemical equation. A balanced chemical equation is one in which the number of atoms in each of the molecules is the same on both sides of the equation.

Answer to Problem 82A

The mass of nitric acid is $326\text{g}$ .

Explanation of Solution

The mass of ammonia is $\text{88}\text{.0 g}$ .

Molar mass of nitrogen is $14.0\text{g}$ .

Molar mass of ammonia is $17.0\text{g}$ .

Molar mass of nitric acid is $63\text{g}$ .

The balanced chemical equation is as follows:

  $\begin{array}{l}{\text{4NH}}_{\text{3}}{\text{+5O}}_{\text{2}}\to 4{\text{NO+6H}}_{\text{2}}\text{O}\hfill \\ {\text{2NO+O}}_{\text{2}}\to 2{\text{NO}}_{\text{2}}\hfill \\ {\text{3NO}}_{\text{2}}{\text{+H}}_{\text{2}}\text{O }\to 2{\text{HNO}}_{\text{3}}\text{+NO}\hfill \end{array}$

The moles of nitric acid is given as follows:

  $88\cancel{\text{g}{\text{NH}}_3}\times \frac{14\cancel{\text{g}\text{N}}}{17\cancel{\text{g}{\text{NH}}_3}}\times \frac{63\text{g}{\text{HNO}}_3}{14\cancel{\text{g}\text{N}}}=326\text{g}{\text{HNO}}_3$

(c)

Interpretation Introduction

Interpretation: The mass of ammonia is to be calculated.

Concept Introduction: Reactants, products, and an arrow indicating the reaction's direction make up a chemical equation. A balanced chemical equation is one in which the number of atoms in each of the molecules is the same on both sides of the equation.

Answer to Problem 82A

The mass of ammonia is $189\text{g}$ .

Explanation of Solution

The concentrated nitric acid used is 70%.

Mass of concentrated nitric acid is $1.00\text{kg}$ .

The mass of concentrated nitric acid prepared is $700\text{g}$ (70% of $1.00\text{kg}$ ).

The mass of ammonia is $\text{88}\text{.0 g}$ .

The mass of nitric acid is $326\text{g}$ .

The balanced chemical equation is as follows:

  $\begin{array}{l}{\text{4NH}}_{\text{3}}{\text{+5O}}_{\text{2}}\to 4{\text{NO+6H}}_{\text{2}}\text{O}\hfill \\ {\text{2NO+O}}_{\text{2}}\to 2{\text{NO}}_{\text{2}}\hfill \\ {\text{3NO}}_{\text{2}}{\text{+H}}_{\text{2}}\text{O }\to 2{\text{HNO}}_{\text{3}}\text{+NO}\hfill \end{array}$

The moles of ammonia is given as follows:

  $700\cancel{\text{g}{\text{HNO}}_3}\times \frac{88\text{g}{\text{NH}}_3}{326\cancel{\text{g}{\text{HNO}}_3}}=189\text{g}{\text{NH}}_3$