Question

According to John Dalton’s observations when elements combine in a compound

Answer 1

Answer: When elements combine in a compound, the ratio of their masses is always the same

Explanation:

Dalton's theory is based on mainly two laws:

• Law of conservation of mass
• Law of constant composition.

Law of conservation of mass states that mass can neither be created nor be destroyed, but it can transformed from one form to another form.

Law of constant composition states that a compound always contain the elements in the fixed ratio by their masses.

For Example: In water $(H_2O)$, the hydrogen and oxygen are present in the fixed ratio of 1 : 9 by their mass.

Hence, when elements combine in a compound, the ratio of their masses is always the same

Answer 2

The answer is A.) The ratio of thier masses is always the same