Question

In a compound A, $1.00\text{g}$ of nitrogen combines with $0.57\text{g}$ of oxygen. In a compound B, $2.00\text{g}$ of nitrogen combines with $2.24\text{g}$ of oxygen. In a compound C, $3.00\text{g}$ of nitrogen combines with $5.11\text{g}$ of oxygen. These data shows which of the following laws?

• A. Law of constant proportions
• B. Law of multiple proportions
• C. Law of reciprocal proportions
• D. Dalton’s law of partial pressure

Answer 1

The correct option is B Law of multiple proportions

According to the question,
$CompoundA\Rightarrow 1\text{g}of{N}_2+0.57\text{g}of{O}_2$
$CompoundB\Rightarrow 2\text{g}of{N}_2+2.24\text{g}of{O}_2$
$\therefore 1\text{g}$ of $N_2$ will require $\frac{1\times 2.24}{2}=1.12\text{g}$ of $O_2$
$CompoundC\Rightarrow 3\text{g}of{N}_2+5.11\text{g}of{O}_2$
$\therefore 1\text{g}$ of $N_2$ will require $\frac{1\times 5.11}{3}=1.70\text{g}$ of $O_2$
The ratio of $O_{2}inA,BandC=0.57:1.12:1.7\approx 1:2:3$
Therefore, the given results obey the law of multiple proportions.