Identify from following phenomena that occures when charcoal is added to methylene blue solution and shaken, it becomes colourless after some time.

When charcoal is added to a methylene blue solution and shaken, the dye molecules of methylene blue accumulate on the surface of the charcoal.

This phenomenon, where molecules of a substance concentrate at the surface of a solid or liquid rather than in the bulk, is known as adsorption.

As a result of the adsorption of methylene blue molecules onto the charcoal surface, the solution becomes colourless.

Answer: Adsorption