jan 1, 1904 - The "raisin bun" model.

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J.J. Thomson discovered very light negative particles which are called electrons. He also did many experiments with beams of positive particles, later called protons. He updated the model once again with this new information but renamed it the "raisin bun" model. He stated:
Atoms contain particles called electrons
Electrons have a small mass and a negative charge.
The rest of the atom is a sphere of positive charge
The electrons are embedded in this sphere, so that the resulting atoms are neutral or uncharged.

At around the same time, a Japanese scientist, H.Nagaoks modelled the atom as a large positive sphere surrounded by a ring of negative electrons. He compared it to the planet Saturn.
So, throughout this period of time people kept making changes to the atomic model which was now called the "raisin bun model". Science kept getting more snd more modern throughout the years.

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