Question

Which parts of Dalton's atomic theory had to be revised? A. Atoms are tiny indivisible particles. B. Atoms of the same element are identical. C. Compounds are molecules made by uniting atoms. D. Atoms of different elements can combine with one another in simple ratios.

Answer 1

Answer: Atoms are indivisible particles.

Answer 2

A. Atoms are indivisible particles.
This was revised after the discovery of Protons, Neutrons, and Electrons. Which, in part, can be further broken down into Quarks (for the exception of the electron, as it is a Lepton).