EVERYDAY SCIENCE

Detailed explanation-1: -The bromine loses its original red-brown color to give a colorless liquid. In the case of the reaction with ethene, 1, 2-dibromoethane is formed. This decoloration of bromine is often used as a test for a carbon-carbon double bond.

Detailed explanation-2: -The two bromine atoms are attached to both carbon atoms containing double bonds. As a result, the bromine water loses its original red-brown or orange colour to give a colourless liquid.

Detailed explanation-3: -When bromine water (which is a solution of bromine in water) is added to ethene, it forms 1, 2-dibromoethane and the solution becomes colourless, i.e., the reddish-brown colour of bromine is discharged. This reaction is used as a test for unsaturation.

Detailed explanation-4: -The bromine water turns colourless confirming the presence of an alkene. The bromine atoms break the carbon–carbon double bond and from C–Br bonds. This type of reaction is called an addition reaction and the addition of bromine to an alkene is called bromination.

Detailed explanation-5: -The bromine loses its original red-brown colour to give a colourless liquid. In the case of the reaction with ethene, 1, 2-dibromoethane is formed. This decolourisation of bromine is often used as a test for a carbon-carbon double bond.