Chapter 7, Problem 41A

(a)

Interpretation Introduction

Interpretation:

A balanced chemical equation corresponding to the combustion of liquid benzene needs to be presented.

Concept Introduction:

• A chemical reaction is expressed as a chemical equation having reactants and products on left and right side of the reaction arrow respectively.

  $\text{Reactants }\to \text{ Products}$

• A balanced chemical equation is one in which the number of atoms of various elements on the reactants side is equal to that on the product side. It depicts the stoichiometry of a given reaction.
• The equations are balanced in two steps:

1) Balance the atoms by matching the number of atoms of each type on the reactants and product side.

2) Adjust the coefficients to the smallest whole number. A coefficient of '1' is implied and therefore not explicitly written.

Answer to Problem 41A

  ${\text{C}}_6{\text{H}}_6\text{(l) + 7}{\text{.5O}}_{\text{2}}\text{(g) }\to {\text{ 6CO}}_2{\text{ (g) + 3H}}_{\text{2}}\text{O(g)}$

Explanation of Solution

The given equation involves the reaction between benzene liquid and oxygen to form carbon dioxide gas and water vapor. The reactants and products are:

Reactants:

  $\begin{array}{l}{\text{Benzene, liquid - C}}_6{\text{H}}_6(\text{l})\\ {\text{Oxygen, gas - O}}_{\text{2}}\text{ (g)}\end{array}$

Products:

  $\begin{array}{l}{\text{Carbon dioxide, gas - CO}}_2\text{(g)}\\ {\text{Water vapor - H}}_{\text{2}}\text{O (g)}\end{array}$

Unbalanced equation:

  ${\text{C}}_6{\text{H}}_6{\text{(l) + O}}_{\text{2}}\text{(g) }\to {\text{ CO}}_2{\text{ (g) + H}}_{\text{2}}\text{O(g)}$

The above equation is not balanced since the number of C, H and O atoms on the reactants side is 6, 6 and 2 respectively while that on the products side is 1, 2 and 3. In order to balance the above equation, multiply O₂ by 7.5, CO₂ by 6 and H₂O by 3 to get:

  ${\text{C}}_6{\text{H}}_6\text{(l) + 7}{\text{.5O}}_{\text{2}}\text{(g) }\to {\text{ 6CO}}_2{\text{ (g) + 3H}}_{\text{2}}\text{O(g)}$

(b)

Interpretation Introduction

Interpretation:

A balanced chemical equation corresponding to the combustion of butane gas needs to be presented.

Concept Introduction:

• A chemical reaction is expressed as a chemical equation having reactants and products on left and right side of the reaction arrow respectively.

  $\text{Reactants }\to \text{ Products}$

• A balanced chemical equation is one in which the number of atoms of various elements on the reactants side is equal to that on the product side. It depicts the stoichiometry of a given reaction.
• The equations are balanced in two steps:

1) Balance the atoms by matching the number of atoms of each type on the reactants and product side.

2) Adjust the coefficients to the smallest whole number. A coefficient of '1' is implied and therefore not explicitly written.

Answer to Problem 41A

  ${\text{C}}_4{\text{H}}_{10}\text{(g) + 6}{\text{.5O}}_{\text{2}}\text{(g) }\to {\text{ 4CO}}_2{\text{ (g) + 5H}}_{\text{2}}\text{O(g)}$

Explanation of Solution

The given equation involves the reaction between butane gas and oxygen to form carbon dioxide gas and water vapor. The reactants and products are:

Reactants:

  $\begin{array}{l}{\text{Butane, gas - C}}_4{\text{H}}_{10}(\text{g})\\ {\text{Oxygen, gas - O}}_{\text{2}}\text{ (g)}\end{array}$

Products:

  $\begin{array}{l}{\text{Carbon dioxide, gas - CO}}_2\text{(g)}\\ {\text{Water vapor - H}}_{\text{2}}\text{O (g)}\end{array}$

Unbalanced equation:

  ${\text{C}}_4{\text{H}}_{10}{\text{(g) + O}}_{\text{2}}\text{(g) }\to {\text{ CO}}_2{\text{ (g) + H}}_{\text{2}}\text{O(g)}$

The above equation is not balanced since the number of C, H and O atoms on the reactants side is 4, 10 and 2 respectively while that on the products side is 1, 2 and 3. In order to balance the above equation, multiply O₂ by 6.5, CO₂ by 4 and H₂O by 5 to get:

  ${\text{C}}_4{\text{H}}_{10}\text{(g) + 6}{\text{.5O}}_{\text{2}}\text{(g) }\to {\text{ 4CO}}_2{\text{ (g) + 5H}}_{\text{2}}\text{O(g)}$

(c)

Interpretation Introduction

Interpretation:

A balanced chemical equation corresponding to the combustion of sucrose needs to be presented.

Concept Introduction:

• A chemical reaction is expressed as a chemical equation having reactants and products on left and right side of the reaction arrow respectively.

  $\text{Reactants }\to \text{ Products}$

• A balanced chemical equation is one in which the number of atoms of various elements on the reactants side is equal to that on the product side. It depicts the stoichiometry of a given reaction.
• The equations are balanced in two steps:

1) Balance the atoms by matching the number of atoms of each type on the reactants and product side.

2) Adjust the coefficients to the smallest whole number. A coefficient of '1' is implied and therefore not explicitly written.

Answer to Problem 41A

  ${\text{C}}_{\text{12}}{\text{H}}_{\text{22}}{\text{O}}_{\text{11}}{\text{(s) + 12O}}_{\text{2}}\text{(g)}\to {\text{12CO}}_{\text{2}}{\text{(g) + 11H}}_{\text{2}}\text{O(g) }$

Explanation of Solution

The given equation involves the reaction between solid sucrose and oxygen to form carbon dioxide gas and water vapor. The reactants and products are:

Reactants:

  $\begin{array}{l}{\text{Sucrose, solid - C}}_{\text{12}}{\text{H}}_{\text{22}}{\text{O}}_{\text{11}}\text{(s)}\\ {\text{Oxygen, gas - O}}_{\text{2}}\text{ (g)}\end{array}$

Products:

  $\begin{array}{l}{\text{Carbon dioxide, gas - CO}}_2\text{(g)}\\ {\text{Water vapor - H}}_{\text{2}}\text{O (g)}\end{array}$

Unbalanced equation:

  ${\text{C}}_{\text{12}}{\text{H}}_{\text{22}}{\text{O}}_{\text{11}}{\text{(s) + O}}_{\text{2}}\text{(g)}\to {\text{CO}}_{\text{2}}{\text{(g) + H}}_{\text{2}}\text{O(l) }$

The above equation is not balanced since the number of C, H and O atoms on the reactants side is 12, 22 and 13 respectively while that on the products side is 1, 2 and 3. In order to balance the above equation, multiply O₂ by 12, CO₂ by 12 and H₂O by 11 to get:

  ${\text{C}}_{\text{12}}{\text{H}}_{\text{22}}{\text{O}}_{\text{11}}{\text{(s) + 12O}}_{\text{2}}\text{(g)}\to {\text{12CO}}_{\text{2}}{\text{(g) + 11H}}_{\text{2}}\text{O(l) }$

(d)

Interpretation Introduction

Interpretation:

A balanced chemical equation corresponding to the combustion of iron needs to be presented.

Concept Introduction:

• A chemical reaction is expressed as a chemical equation having reactants and products on left and right side of the reaction arrow respectively.

  $\text{Reactants }\to \text{ Products}$

• A balanced chemical equation is one in which the number of atoms of various elements on the reactants side is equal to that on the product side. It depicts the stoichiometry of a given reaction.
• The equations are balanced in two steps:

1) Balance the atoms by matching the number of atoms of each type on the reactants and product side.

2) Adjust the coefficients to the smallest whole number. A coefficient of '1' is implied and therefore not explicitly written.

Answer to Problem 41A

  ${\text{4Fe(s) + 3O}}_{\text{2}}\text{(g)}\to 2{\text{Fe}}_{\text{2}}{\text{O}}_3\text{(s) }$

Explanation of Solution

The given equation involves the reaction between solid iron and oxygen to form solid iron (III) oxide. The reactants and products are:

Reactants:

  $\begin{array}{l}\text{Iron, solid - Fe (s)}\\ {\text{Oxygen, gas - O}}_{\text{2}}\text{ (g)}\end{array}$

Products:

  ${\text{iron (III) oxide, solid - Fe}}_{\text{2}}{\text{O}}_3\text{(s)}$

Unbalanced equation:

  ${\text{Fe(s) + O}}_{\text{2}}\text{(g)}\to {\text{Fe}}_{\text{2}}{\text{O}}_3\text{(s) }$

The above equation is not balanced since the number of Fe and O atoms on the reactants side is 1 and 2 respectively while that on the products side is 2 and 3. In order to balance the above equation, multiply Fe by 4, O₂ by 3 and Fe₂O₃ by 2 and to get:

  ${\text{4Fe(s) + 3O}}_{\text{2}}\text{(g)}\to 2{\text{Fe}}_{\text{2}}{\text{O}}_3\text{(s) }$

(d)

Interpretation Introduction

Interpretation:

A balanced chemical equation corresponding to the combustion of iron (II) oxide needs to be presented.

Concept Introduction:

• A chemical reaction is expressed as a chemical equation having reactants and products on left and right side of the reaction arrow respectively.

  $\text{Reactants }\to \text{ Products}$

• A balanced chemical equation is one in which the number of atoms of various elements on the reactants side is equal to that on the product side. It depicts the stoichiometry of a given reaction.
• The equations are balanced in two steps:

1) Balance the atoms by matching the number of atoms of each type on the reactants and product side.

2) Adjust the coefficients to the smallest whole number. A coefficient of '1' is implied and therefore not explicitly written.

Answer to Problem 41A

  ${\text{4FeO(s) + O}}_{\text{2}}\text{(g)}\to 2{\text{Fe}}_{\text{2}}{\text{O}}_3\text{(s) }$

Explanation of Solution

The given equation involves the reaction between solid iron (II) oxide and oxygen to form solid iron (III) oxide. The reactants and products are:

Reactants:

  $\begin{array}{l}\text{Iron (II) oxide, solid - FeO (s)}\\ {\text{Oxygen, gas - O}}_{\text{2}}\text{ (g)}\end{array}$

Products:

  ${\text{iron (III) oxide, solid - Fe}}_{\text{2}}{\text{O}}_3\text{(s)}$

Unbalanced equation:

  ${\text{FeO(s) + O}}_{\text{2}}\text{(g)}\to {\text{Fe}}_{\text{2}}{\text{O}}_3\text{(s) }$

The above equation is not balanced since the number of Fe atom on the reactants side is 1 while that on the products side is 2. In order to balance the above equation, multiply FeO by 4, and Fe₂O₃ by 2 and to get:

  ${\text{4FeO(s) + O}}_{\text{2}}\text{(g)}\to 2{\text{Fe}}_{\text{2}}{\text{O}}_3\text{(s) }$