Displacement reaction is a chemical reaction in which a more reactive element displaces a less reactive element from its compound. The test tubes contain (L) bromine and (R) iodine that have been displaced from potassium bromide and potassium iodide solutions by a few drops of chlorine water, a halogen. A comparative darkening of the solution is a simple indication that the displacement has occurred. Chlorine is more reactive than bromine and iodine and is able to displace them. The order of reactivity of these Group 7 halogen elements from highest to lowest is chlorine, bromine and iodine.
Model release not required. Property release not required.