Question

What is the minimum number of carbon atoms of an alkane must have to form an isomer?

• A. 4
• B. 3
• C. 2
• D. 1

Answer 1

The correct option is A 4

Branching is not possible with carbon $1,2$ and $3$.

(Refer to Image 1)

Minimum $4$ carbons are required to show chain isomerism.

(Refer to Image 2)