Question

Which compound has alkyne group?

• A. $C_7{H}_{14}$
• B. $C_{10}{H}_{22}$
• C. $C_9{H}_{16}$
• D. $C_{16}{H}_{32}$

Answer 1

The correct option is C

${\mathrm{C}}_9{\mathrm{H}}_{16}$

Explanation for correct option:

(C)

Unsaturated hydrocarbon

• Hydrocarbons are class of organic compounds made up of only Carbon and Hydrogen atoms.
• Unsaturated hydrocarbons are those that have double or triple bonds between adjacent carbon atoms.
• An unsaturated hydrocarbon with at least one carbon-carbon double bond between two carbon atoms is referred to as an alkene.
• The general formula for an alkyne is ${\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}-2}$, where n is the number of the carbon atom.
• Thus, the hydrocarbon ${\mathrm{C}}_9{\mathrm{H}}_{16}$ satisfies the general formula of alkyne, ${\mathrm{C}}_9{\mathrm{H}}_{2\times 9-2}={\mathrm{C}}_9{\mathrm{H}}_{16}$. Thus, it belongs to an alkyne group.

Explanation for incorrect options:

(A)

• The hydrocarbon ${\mathrm{C}}_7{\mathrm{H}}_{14}$ satisfies the general formula for alkene $\left({\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}}\right)$.
• Thus, ${\mathrm{C}}_7{\mathrm{H}}_{14}$ is an alkene.

(B)

• The hydrocarbon ${\mathrm{C}}_{10}{\mathrm{H}}_{22}$ satisfies the general formula for alkane $\left({\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}+2}\right)$.
• So,${\mathrm{C}}_{10}{\mathrm{H}}_{22}$ is an alkane.

(D)

• The hydrocarbon ${\mathrm{C}}_{16}{\mathrm{H}}_{32}$ satisfies the general formula for alkene $\left({\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}}\right)$.
• So, ${\mathrm{C}}_{16}{\mathrm{H}}_{32}$ is an alkene.

Hence, option (C) is correct. ${\mathrm{C}}_9{\mathrm{H}}_{16}$ is an alkyne.