Question

2-Pentene contains:

• A. 15 \( \sigma \)- and one \( \pi \)-bond
• B. 14 \( \sigma \)- and one \( \pi \)-bond
• C. 15 \( \sigma \)- and two \( \pi \)-bonds
• D. 14 \( \sigma \)- and two \( \pi \)-bonds

Hint:

Alkanes contain only sigma bonds, while alkenes contain one pi bond per double bond in addition to sigma bonds.

Answer 1

The Correct Option is B

Step 1: Understanding bonding in 2-Pentene.
- 2-Pentene (\( C_5H_{10} \)) is an alkene with a double bond between C2 and C3.
- A single bond is a sigma (\(\sigma\)) bond, while a double bond consists of one \(\sigma\) and one \(\pi\) bond.
Step 2: Counting the bonds.
1. C-C and C-H single bonds are sigma (\(\sigma\)) bonds.
2. One double bond (C2=C3) contributes one sigma and one pi bond.
3. Total sigma bonds = 14.
4. Total pi bonds = 1.
Step 3: Identifying the correct answer.
- Since 2-Pentene has 14 sigma and one pi bond, the correct option is (B).