Question

The composition of mercurous chloride is $84.92\%$ mercury and $15.08\%$ chlorine. The composition of mercuric chloride is $73.08\%$ mercury and $26.020\%$ chlorine. This illustrates:

• A. Law of definite proportion
• B. Law of multiple proportion
• C. Law of reciprocal relation
• D. Law of conservation of mass

Answer 1

The correct option is B Law of multiple proportion

Let us assume the amount of mercurous chloride and mercuric chloride be $100g$

Therefore, mass of mercury in mercurous chloride = $84.92g$.
Mass of chloride in mercurous chloride = $15.08g$

Similarly, mass of mercury in mercuric chloride = $73.08g$
mass of chloride in mercuric chloride $=26.02g$
Mass of Cl that combines with $84.92g$ mercury in
mercuric chloride $=\frac{84.92\times 26.02}{73.08}$
= $30.16g$
In the question, the ratio of masses of $Cl$ that combines with the fixed mass of $Hg$, (84.92 g) is 15.08 : 30.16 or 1: 2 which is a whole number ratio. Hence this illustrates law of multiple proportions.