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Democritus
Democritus believed that everything is made up of atoms and that these atoms were indestructible, unable to be separated and that between these atoms lay empty space. -
John Dalton
Dalton formed an idea that all atoms of a given element were identical in properties and mass and that compounds were formed by a different combination of two or more different types of atoms -
Thomson
Thomson completely changed the view of an atom by discovering electrons, his theory proposed that atoms could be cut and that they were made of smaller things such as protons and electrons. -
Rutherford
Rutherford described his atomic theory as the atom having a central nucleus surrounded by negative orbiting electrons. This model suggested that the mass of the atom was mostly in the nucleus and the rest was mostly empty space. -
Bohr
Neils Bohr developed on Rutherford’s model by suggesting that electrons orbit the nucleus without losing energy but could only move in fixed orbits of specific energies. And that electrons with lower energy would orbit close to the nucleus whilst the higher energy electrons orbited further away. -
Quantum Model of the Atom
Louis de Broglie suggested that electrons could act as both particles and waves, like light.
