Look in a cookbook for the temperature used for baking bread and convert to degrees centigrade. Obtain a sample of KBrO₃ and place in a test tube fitted with a one hole stopper and a glass tube coming out of the stopper. Connect the glass tube to a piece of rubber tubing and place the end of the rubber tubing under an inverted water-filled graduated cylinder in a pan of water (to collect any oxygen gas given off in the reaction). Heat the test tube containing the KBrO₃ in a sand bath at the baking temperature (determined previously) and measure the amount of oxygen given off.