Question

Dalton's atomic theory successfully explained

(i) Law of conservation of mass

(ii) Law of constant composition

(iii) Law of radioactivity

(iv) Law of multiple proportion

• A. (i),(ii), and (iii)
• B. (i),(iii), and (iv)
• C. (ii),(iii), and (iv)
• D. (i),(ii), and (iv)

Answer 1

The correct option is D

(i),(ii), and (iv)

The correct option is (D).

Explanation of the correct option:

John Dalton called the smallest particle of a matter an atom. He then proposed an atomic theory which is known as Dalton's atomic theory. The main postulates of his theory are :

1. All matter is made up of very tiny, indivisible, and indestructible particles which are known as atoms.
2. Atoms can neither be created nor be destroyed in a chemical reaction(Law of conservation of mass).
3. Atoms of a single element are identical and atoms of different elements are different in terms of size, mass, and chemical properties.
4. During a compound formation, the atoms combine in constant proportion(Law of constant proportion).
5. Atoms of the same element can combine in more than one ratio to form more than one compound(Law of multiple proportions).

Thus, Dalton's atomic theory successfully explained the law of conservation of mass, the law of constant composition, and the law of multiple proportions.

Hence (i),(ii), and (iv) are correct.