An lmprovement to the Copper Oxidation Experiment

Abstract

The oxidation of has been a common experiment in junior high shcool courses. The experiment is concerned with the law of definite proportion. The powder X-ray diffraction of the product of the copper oxidation reaction revealed that it was a mixture of copper oxide and a considerable amount of unreacted copper. The improved methods described here provide stoichiometric oxidation of the copper powder. Copper powder (1.00g) and silica (0.50g) were mixed in a ceramic crucible. The mixture was heated with a gas funnel. The reaction mixture was vigorously stirred with a stainless-steal spatula during oxidation. Upon heating for a period of 15 min, the reaction mixture came to a red heat. After cooling to room temperature, the reaction mixture was weighted with an electronic balance. The weight of the product was close to its theoretical weight. The same results were obtained by the junior high school students.