Question

Various theories were put forward to study the nature of the atom. The main postulates of Dalton's atomic theory are:

• A. the matter is composed of atoms.
• B. the matter is composed of molecules.
• C. all atoms of an element are identical.
• D. the atoms of different elements vary in size and mass.

Answer 1

Answer: (A), (C), (D)

the matter is composed of atoms.
all atoms of an element are identical.
the atoms of different elements vary in size and mass.

It was John Dalton who firstly developed a theory on the structure of matter, later on, which is known as Dalton's atomic theory.

Dalton's atomic theory:

1. Matter is made up of very small indivisible particles called atoms.

2. All the atoms of a given element are identical in all respect i.e. mass, shape, size, etc.

3. Atoms cannot be created nor destroyed by any chemical process.

4. Atoms of different elements are different in nature.