Drawbacks of Dalton’s Atomic Theory The indivisibility of an atom was proved wrong: an atom can be further subdivided into protons, neutrons and electrons. However an atom is the smallest particle that takes part in chemical reactions. Dalton also claimed that atoms of different elements are different in all respects.

The nucleus contains two types of subatomic particles, protons and neutrons. The protons have a positive electrical charge and the neutrons have no electrical charge. A third type of subatomic particle, electrons, move around the nucleus. The electrons have a negative electrical charge.

While controversial at first, Thomson’s discoveries were gradually accepted by scientists. Eventually, his cathode ray particles were given a more familiar name: electrons. The discovery of the electron disproved the part of Dalton’s atomic theory that assumed atoms were indivisible.

The difference between Thomson’s model of the atom and Rutherford’s model was that Thomson’s model had atoms that have smaller particles called electrons and Rutherford’s model had electrons move about a nucleus. Bohr discovered that electrons are arranged in shells or levels around the nucleus.

Although there were many models, four main ones have led to our current concept of the atom.

• The Plum Pudding Model. The so-called plum pudding model was proposed by the scientist J.J.
• Planetary Model.
• Bohr Model.
• Electron Cloud Model.

Atomic models

• John Dalton’s atomic model. Ilustration of Dalton’s perception of atom.
• Plum pudding model.
• Rutherford’s model of the atom.
• Bohr’s model of the atom.
• Electron Cloud Model/Quantum Mechanics Model of Atom.
• Basic description of the quantum mechanical atomic model:
• Sources:

1 Answer. Samantha C. Erwin Schrodinger’s model of the atom is a more accurate representation of the molecular activity within an atom. His model defeated Bohr’s idea of fixed orbits, thus acknowledging the electrons’ erratic movements.