Chapter 12, Problem 12.70P

Write a balanced equation for the combustion of each sycloalkane.

Interpretation Introduction

(a)

Interpretation:

The balance equation for the combustion of following cycloalkane should be written.

Concept Introduction:

Compounds consist of carbon and hydrogen is known as hydrocarbons. Hydrocarbons are classified as saturated hydrocarbon and unsaturated hydrocarbon. Saturated hydrocarbons are those hydrocarbons in which carbon-carbon single bond is present as carbon is linked with four atoms. Unsaturated hydrocarbons are those hydrocarbons in which carbon-carbon multiple bonds are present that is double and triple bond.

Saturated hydrocarbon is known as alkane having general molecular formula ${\text{C}}_n{\text{H}}_{2n+2}$.

The compounds in which series of atoms are connected to form a ring is known as cyclic compound whereas the compounds which are open chain compounds and their atoms doesn't form a ring is known as acyclic compounds.

The chemical reaction which involves the reaction of alkane and oxygen, results in the formation of carbon dioxide gas and water vapor is known as combustion reaction. The combustion reaction is an exothermic reaction.

The general reaction of combustion of alkane is:

  ${\text{C}}_n{\text{H}}_{2n+2}+\left[n+\frac{(n+1)}{2}\right]{\text{O}}_{\text{2}}(g)\to n{\text{CO}}_{\text{2}}(g)+(n+1){\text{H}}_{\text{2}}\text{O}(g)$

A reaction is said to be balanced, if the number of atoms of each element on the product side and one the reactant side of a chemical reaction are equal.

Answer to Problem 12.70P

  ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}(l)+9{\text{O}}_{\text{2}}(g)\to 6{\text{CO}}_{\text{2}}(g)+6{\text{H}}_{\text{2}}\text{O}(g)$

Explanation of Solution

Cyclic alkane is defined as an alkane in which series of atoms are combined to form a ring.

The general molecular formula of cyclic alkane is ${\text{C}}_n{\text{H}}_{2n}$ where n represents the number of carbon atoms.

The given cycloalkane is:

The chemical formula of the cycloalkane is ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}$.

  ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}$ reacts with oxygen and results in the formation of carbon dioxide gas and water vapor.

The combustion reaction of ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}$ is written as:

  ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}(l)+{\text{O}}_{\text{2}}(g)\to {\text{CO}}_{\text{2}}(g)+{\text{H}}_{\text{2}}\text{O}(g)$

Reactant side Product side

Number of C atoms = 6 Number of C atoms = 1

Number of H atoms = 12 Number of H atoms = 2

Number of O atoms = 2 Number of O atoms = 3

Thus, the above reaction is not balanced. To balance the reaction, multiply 9 with oxygen gas, 6 with carbon dioxide gas and 6 with water vapor.

Therefore, the balanced combustion reaction of ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}$ is written as:

  ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}(l)+9{\text{O}}_{\text{2}}(g)\to 6{\text{CO}}_{\text{2}}(g)+6{\text{H}}_{\text{2}}\text{O}(g)$

Interpretation Introduction

(b)

Interpretation:

The balance equation for the combustion of following cycloalkane should be written.

Concept Introduction:

Compounds consist of carbon and hydrogen is known as hydrocarbons. Hydrocarbons are classified as saturated hydrocarbon and unsaturated hydrocarbon. Saturated hydrocarbons are those hydrocarbons in which carbon-carbon single bond is present as carbon is linked with four atoms. Unsaturated hydrocarbons are those hydrocarbons in which carbon-carbon multiple bonds are present that is double and triple bond.

Saturated hydrocarbon is known as alkane having general molecular formula ${\text{C}}_n{\text{H}}_{2n+2}$.

The compounds in which series of atoms are connected to form a ring is known as cyclic compound whereas the compounds which are open chain compounds and their atoms doesn't form a ring is known as acyclic compounds.

The chemical reaction which involves the reaction of alkane and oxygen, results in the formation of carbon dioxide gas and water vapor is known as combustion reaction. The combustion reaction is an exothermic reaction.

The general reaction of combustion of alkane is:

  ${\text{C}}_n{\text{H}}_{2n+2}+\left[n+\frac{(n+1)}{2}\right]{\text{O}}_{\text{2}}(g)\to n{\text{CO}}_{\text{2}}(g)+(n+1){\text{H}}_{\text{2}}\text{O}(g)$

A reaction is said to be balanced, if the number of atoms of each element on the product side and one the reactant side of a chemical reaction are equal.

Answer to Problem 12.70P

  ${\text{2C}}_5{\text{H}}_{\text{10}}(l)+15{\text{O}}_{\text{2}}(g)\to 10{\text{CO}}_{\text{2}}(g)+10{\text{H}}_{\text{2}}\text{O}(g)$

Explanation of Solution

Cyclic alkane is defined as an alkane in which series of atoms are combined to form a ring.

The general molecular formula of cyclic alkane is ${\text{C}}_n{\text{H}}_{2n}$ where n represents the number of carbon atoms.

The given cycloalkane is:

The chemical formula of the cycloalkane is ${\text{C}}_5{\text{H}}_{\text{10}}$.

  ${\text{C}}_5{\text{H}}_{\text{10}}$ reacts with oxygen and results in the formation of carbon dioxide gas and water vapor.

The combustion reaction of ${\text{C}}_5{\text{H}}_{\text{10}}$ is written as:

  ${\text{C}}_5{\text{H}}_{\text{10}}(l)+{\text{O}}_{\text{2}}(g)\to {\text{CO}}_{\text{2}}(g)+{\text{H}}_{\text{2}}\text{O}(g)$

Reactant side Product side

Number of C atoms = 5 Number of C atoms = 1

Number of H atoms = 10 Number of H atoms = 2

Number of O atoms = 2 Number of O atoms = 3

Thus, the above reaction is not balanced. To balance the reaction, multiply ${\text{C}}_5{\text{H}}_{\text{10}}$ with 2, 15 with oxygen gas, 10 with carbon dioxide gas and 10 with water vapor.

Therefore, the balanced combustion reaction of ${\text{C}}_5{\text{H}}_{\text{10}}$ is written as:

  ${\text{2C}}_5{\text{H}}_{\text{10}}(l)+15{\text{O}}_{\text{2}}(g)\to 10{\text{CO}}_{\text{2}}(g)+10{\text{H}}_{\text{2}}\text{O}(g)$