Question

Give two drawbacks of Dalton’s atomic theory.

Answer 1

The drawbacks of Dalton's atomic theory:

1. Dalton's theory states that atoms cannot be divided but this theory was proved wrong with the discovery of proton, electron, and neutrons within an atom.
2. Dalton's theory states that atoms of different elements are different in all aspects but this theory was also proved wrong with the introduction of isobars, in which different elements may have the same atomic mass. e.g. Argon$\left(\mathrm{Ar}\right)$ and Calcium $\left(\mathrm{Ca}\right)$ have atomic mass of $40\mathrm{amu}$.