Question

How many chain isomers does a compound having molecular formula ${\text{C}}_5{\text{H}}_{10}$ has?

• A. 5
• B. 4
• C. 3
• D. 2

Answer 1

The correct option is B 4

The compounds having the same molecular formula but a difference in chain structure are called chain isomers. The following compounds have the same molecular formula ${\text{C}}_5{\text{H}}_{10}$ but different chain structures.
a) 1- pentene
b) 2- pentene
c) 2- methyl- 1- butene
d) 2- methyl- 2- butene

The structures of these compounds are given below:

Hence, the compound having molecular formula ${\text{C}}_5{\text{H}}_{10}$ has four chain isomers.