Question

Analyze the compound $CH_3CH_2CH=CHCH_3$. What is the IUPAC name for this compound, and what functional group is present?

• A. 3-pentene, alkane
• B. 2-butene, alkene
• C. 2-pentene, alkene
• D. 3-butene, alkyne

Answer 1

Answer: (C)

2-pentene, alkene

Answer 2

The compound $CH_3CH_2CH=CHCH_3$ has a 5-carbon chain with a carbon-carbon double bond. Numbering from the end that gives the double bond the lowest position (from right to left), the double bond is at position 2. Thus, the IUPAC name is 2-pentene. The functional group is an alkene due to the presence of the carbon-carbon double bond.