Two oxide samples of lead were heated in the current of hydrogen and were reduced to the metallic lead. The following data were obtained
(i) Weight of yellow oxide taken = 3.45 gm, Loss in weight in reduction = 0.24 gm
(ii) Weight of brown oxide taken = 1.227 gm, Loss in weight in reduction = 0.16 gm.
Show that the data illustrates the law of multiple proportion.

Explanation

When the oxide of lead is reduced in the current of hydrogen, metallic lead is formed. Definitely, the loss in weight in reduction is due to removal of the oxygen present in the oxide, to combine with the hydrogen. Therefore,
the composition of the yellow oxide is: oxygen = 0.24 gm and lead = 3.45 – 0.24 = 3.21 gm.
The mass ratio of lead and oxygen,
`r_(1)=m_(Pb)/m_(O)=3.21/0.244=13.375/1.000`
and the compositon of the brown oxide is :
oxygen = 0.16 gm and lead
= 1.227 – 0.16 = 1.067 gm.
The mas ratio of lead and oxygen,
`r_(2)=m_(Pb)/m_(O)=1.067/0.16= 6.669/1.000`
Now, `r_(1):r_(2)=13.375:6.6669=2.1` (simple ratio) and hence the data illustrates the law of multiple proportion.