Describe the main points of dalton's atomic theory and then explain what points of the theory are still accepted in modern atomic theory and what points have been changed as the result of later experiments and discoveries.

Explanation:

The postulates of the Dalton's Atomic Theory are;

Points changed;

1. The indivisibility of an atom was proved wrong: advances in the field of science revealed an atom can be further subdivided into protons, neutrons and electrons.

2. According to Dalton, the atoms of same element are similar in all respects. However, atoms of some elements vary in their masses and densities. The discovery of isotopes proved this to be wrong. Isotopes are atoms with different mass number but same atomic number For example, hydrogen has three isotopes with mass numbers 1, 2 and 3.

3. Nuclear chemistry shows that indeed atoms can be destroyed (Nuclear Fission). The destroyed atoms is converted into energy.

4. According to Dalton, atoms of different elements combine in simple whole number ratios to form compounds. However this is not the case in complex organic reactions involving compounds like RNA, Polymers etc.

Point Still Accepted;

1. An atom is indeed the smallest particle that takes part in chemical reactions.

2. A chemical reaction results in the rearrangement of atoms in the reactant and product compounds.