Question

How would you distinguish between the following pairs of compounds using simple chemical tests? Tell what you would do and what you would see.

(a) Cyclopentene and cyclopentane

Short answer

Cyclopentene shows the bayer's test and bromine water test but cyclopentane does not show this test.

Step-by-step solution

Bayer's test

Cyclopentene is an unsaturated compound having a double bond, and cyclopentane is a saturated compound having a single bond.

Cyclopentene on reaction with ${\mathrm{KMnO}}_4$ forms 1,2 diol and decolorizes the purple color of potassium permanganate, but cyclopentane does not show decolorization.

Bromine water test

Cyclopentene is an unsaturated compound having a double bond and cyclopentane is a saturated compound having a single bond.

Cyclopentene on reaction with bromine water shows decolorization but when cyclopentane reacts with bromine water no decolorization is observed.