Question

The position isomer of the given compound is .

• A. but-1-ene
• B. but-2-ene
• C. prop-2-ene

Answer 1

The correct option is B but-2-ene

Compounds having the same structure of the carbon chain but differing only in the position of the multiple (double or triple) bonds or the functional group are called positional isomers.
The given compound is but-1-ene as it has unsaturation position 1.
The only possible position isomer for the given compound is:
The nomenclature of this isomer is but-2-ene.