e REDUCTION OF POTASSIUM PERMANGANATE WITH SULFUR DIOXIDE i Add 10 mL of 01M solution of potassium permanganate and 10 mL 3M solution of dilute sulphuric acid to 200 mL of water containing sulphur dioxide The solution will gradually become colourless as the sulphur dioxide reacts with the permanganate The experiment can be continued further by stirring in a 025M solution of barium chloride when the solution will become milky due to the formation of barium sulphate ii The generator used in experiment 275B is a convenient piece of apparatus for giving a continuous supply of sulphur dioxide for bleaching Bowers and other plants The gas from the generator is passed through a jar containing the plant and excess gas is absorbed in water The colour of the bleached plant can easily be regenerated by placing the plant in a solution of hydrogen peroxide This experiment could be used as an introduction to the processes of reduction and oxidation