Halogen displacement

A halogen displacement experiment is a common experiment in chemistry that involves the reaction between a halogen and a salt solution of another halogen. Here are the general steps for carrying out a halogen displacement experiment:

Materials needed:

Potassium halide salt (e.g. potassium chloride, KCl, Potassium Bromide, KBr, Potassium Iodide KI)

Halogen solution (e.g. chlorine water, Cl₂(aq), Bromine water, Br₂(aq), Iodine water, I₂(aq))

Spotting Tile

Universal indicator paper

Safety goggles and lab coat

Procedure:

Add a few drops of each potassium halide salt solution to 3 wells on the spotting tile.

Add a few drops of halogen solution (e.g. chlorine water) to each well.

Repeat so that all combinations of halogen water has the opportunity to react with the potassium halide solutions.

Observe and record the reaction in each well. A reaction is indicated by a change in color, the formation of a precipitate or gas bubbles. Hint. If you add a colourless liquid and the colour of the other liquid gets lighter it might just be dilution.

Test the pH of the solutions in each test tube using universal indicator paper

Compare the results in each well. If a halogen displacement reaction has occurred, the halogen in the salt has been displaced by the halogen in the solution.

Remember to wear safety goggles and a lab coat when conducting any chemical experiment, and to dispose of chemicals properly after the experiment.