Famous Scientist Atomic Theory

John Dalton

John Dalton

5 Parts of Dalton's Theory

Model is known as the Billiard Ball.

1. All matter is made up of tiny, indivisible particles called atoms. (FALSE)

2. Atoms of the same element are identical. (FALSE - ISOTOPES)

3. In a chemical reaction, atoms are combined, rearranged, or separated.

4. Atoms of different elements chemically combine to form a whole number ratio called compounds

5. Atoms cannot be created or destroyed

JJ Thomson

Discovered Electrons (negative charge) by using cathode ray tube.

JJ Thomson Model

His model was Plum Pudding Model

Rutherford

Discovered the nucleus and performed the gold foil experiment. Most of particles went through the gold so it shows atom is mostly empty. But some of them deflected and others bounced back. If the atom had very dense center and this when he discovered the nucleus.

Rutherford Model

This what the model looks like

Niels Bohr (Bohr Model)

Electrons orbited the nucleus like planets do with sun. Also called the Planetary Model.

James Chadwick

Discovered Neutrons and discovered that they have no charge. Also neutrons are found in the nucleus.

Erwin Schrödinger

Created the Wave Model and is which is the current model. Said electrons are found in electron cloud.

Heisenberg

Position and speed of a particle, such as electrons.

Timeline of Atomic Theory

Here’s the timeline of the atomic theory.