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

Postulates of Dalton’s atomic theory.

• The matter is made up of indivisible particles known as atoms.
• The properties of all the atoms of a given element are same including mass. This can also be stated as all the atoms of an element have identical mass while the atoms of different elements have different masses.
• Atoms of different elements combine in fixed ratios to form compounds.
• Atoms are neither created nor destroyed. This implies that during chemical reactions, no atoms are created nor destroyed.
• The formation of new products (compounds) results from the rearrangement of existing atoms (reactants).
• Atoms of an element are identical in mass, size and many other chemical or physical properties, but atoms of two-different elements differ in mass, size and many other chemical or physical properties.

Hence, the correct option is D.