This simple experiment shows the electrolysis of an ionic solid, the fading of the blue colour shows the removal of Cu2+ ions and the copper can be seen appearing on the anode.
In addition, the chlorine given off will bleach blue litmus and displace iodine from the potassium iodide solution and bromine from the potassium bromide solution.
It is carried out in a petri dish and the small scale means that the amount of chlorine evolved, even by a whole class, is low enough for it to be carried out in the open laboratory
