Give a test that can be used to differentiate between saturated and unsaturated hydrocarbons.

One common test to differentiate between saturated and unsaturated hydrocarbons is the bromine water test, also known as the bromine test. This test is particularly effective in distinguishing between the two types of hydrocarbons based on their ability to undergo addition reactions with bromine. Here’s how the test works:

1. Bromine Water (Br2) Test:

a. Saturated Hydrocarbons (Alkanes):

. Saturated hydrocarbons, such as alkanes, do not readily react with bromine water.
. When a saturated hydrocarbon is mixed with bromine water, there is no observable color change. The bromine water retains its original orange or reddish-brown color.

b. Unsaturated Hydrocarbons (Alkenes and Alkynes):

. Unsaturated hydrocarbons, such as alkenes and alkynes, can readily react with bromine water.
. When an unsaturated hydrocarbon is mixed with bromine water, a rapid reaction occurs. The bromine molecule (Br2) undergoes an addition reaction with the unsaturated bond in the hydrocarbon, breaking the double or triple bond.
. This reaction causes the bromine water to lose its characteristic color, turning from orange or reddish-brown to colorless. This change in color indicates that the unsaturated hydrocarbon has reacted with the bromine, effectively decolorizing the bromine water.

The bromine water test is a simple and effective way to differentiate between saturated and unsaturated hydrocarbons. Saturated hydrocarbons do not react with bromine water, while unsaturated hydrocarbons cause a visible decolorization of the bromine water due to the addition reaction with the double or triple bond.