Copper gives two oxides. On heating one gram of each in hydrogen, we get 0.888g and 0.798g of the metal respectively. Show that these results are in agreement with law of multiple proportion.

Explanation

In the first oxide, wt of Cu = 0.888g
Wt of oxygen =1-0.888 = 0.112g
0.888g of Cu react with 0.112 of oxygen
1g of Cu would react with 0.126g of oxygen in second oxide
Wt of Cu = 0.798g
Wt of oxygen = 1-0.798 = 0.202g
1g of Cu would react with 202/.798 = 0.253
The different masses of oxygen that react with same mass of copper bear the ratio 0.126:0.253 or 1:2, which is law of multiple proportion.