2.16 g of copper metal, when treated with nitric acid followed by ignition of the nitrate, gave 2.70 g of copper oxide. In another experiment, 1.15 g of copper oxide upon reduction with hydrogen gave 0.92 g of copper. Show that the above data illustrates the law of definite proportions.
% of Cu in copper oxide in 1st case = 2.16×1002.70 = 80 % of oxygen = 20% % of Cu in copper oxide in 2nd case = 0.92×1001.15 = 80 % of oxygen = 20% Thus, the percentage of copper in copper oxide from both experiments is the same. Hence the above data illustrates the law of definite proportions.