Question

Define the law of constant proportions.

Answer 1

Definition:

• Law of Constant Proportions was proposed by Joseph Proust in 1799.
• Also known as the law of definite proportions.
• According to this law, the elements are always present in definite proportions by mass.
• In simpler terms, the proportion of elements by weight in a given compound will always remain exactly the same.

Example:

In a water molecule, the ratio of the mass of hydrogen and mass of oxygen always remains the same which is 1:8 irrespective of the source from which water is taken.