Which suffix is used to indicate the presence of a triple bond in a carbon chain?

The correct option is -yne.

Explanation

In IUPAC nomenclature, hydrocarbons are named based on the type of carbon-carbon bonds present in the chain. The suffix of the parent name indicates the degree of saturation (single, double, or triple bonds).

Option Analysis:

• -yne is Correct: The suffix -yne is used to indicate the presence of a carbon-carbon triple bond (C≡C). Hydrocarbons containing at least one triple bond are classified as alkynes (e.g., Ethyne).
• -ene is Incorrect: The suffix -ene indicates the presence of a carbon-carbon double bond (C=C). These hydrocarbons are classified as alkenes (e.g., Ethene).
• -ane is Incorrect: The suffix -ane indicates that the carbon chain consists exclusively of carbon-carbon single bonds (C-C). These are saturated hydrocarbons known as alkanes (e.g., Ethane).
• -yl is Incorrect: The suffix -yl is used to denote an alkyl group, which is a substituent formed by removing one hydrogen atom from an alkane (e.g., Methyl group derived from Methane).

Key Takeaway:

The primary suffixes for hydrocarbon saturation are -ane (single bond), -ene (double bond), and -yne (triple bond).