Question

State the postulate of Dalton atomic theory.Which of his postulate are not correct at present.

Answer 1

Dalton's atomic theory postulates that the atom is an indivisible structure but he said that atom is a block and a single element consist of nothing
At present we have found that atom is divisible and atom is contains of inner energy elements called proton electron and neutron

Answer 2

Answer:-1)Matter consist of indivisible atoms .

2)all the atoms of a given compound have identical properties including identical mass. Atoms of different element have different atomic mass.

3)compounds are formed when atoms of different elements combine in a fixed ratio.

4)chemical reaction involve reorganisation of atoms. These are neither be created nor destroyed in a chemical reaction.

Second Postulate is not hold correct at present because there are so many isobars of the elements means the elements having same atomic mass but different atomic number.