Question

how will you distinguish between hexane and hexene give chemical test

Answer 1

Bromine water test - Hexane would not decolourise bromine but Hexene would decolourise bromine water
bromine water is brown in colour

Answer 2

The difference between Hexane and Hexene:

To distinguish between hexane and hexene we can perform the Bromine Water Test. Bromine water, brown in colour is decolourised by hexene but not by hexane.

This is because the bromine breaks the double hydrogen bond in hexene (an alkene) to form an alkane.

However, when the compound is already an alkane (in this case hexane) the bromine stays in the solution and the colour is not discharged unlike hexene.