-
400 BCE
Democritus
Democritus was Greek philosopher, who lived around 460-370 BC. Democritus created a theory that everything was made up of small things, small things that are hard and indivisible. Particles of matter moving through empty space, Democritus called them Atoms ( it comes from the greek word Atoma). At first it wasn't accepted and it took around 2,000 years for it to be researched on. Democritus gave us the vital backbone to the atomic theory and how everything was bulit. -
300 BCE
Aristotle
Aristotle was a Greek philosopher who openly opposed the Atomic theory created by Democritus. He believed that instead of atoms, the whole universe was created by essential elements ( water, air, earth, fire). And this was excepted by everyone until later on. -
John Dalton
John Dalton was an English teacher who made many laws for the Atomic Theory of today. Thanks to new experiments and technology, around 1800, John Dalton Proposed the following ideas. 1. Matter is made up of atoms that are indivisible and indestructible, 2. All atoms of an element are the same, 3. Atoms of different elements have different weight and chemical properties, 4. Atoms of different elements combine simple whole numbers to from compounds, and 5. Atoms can't be created or destroyed. -
J.J Thomson
J.J Thomson was an English physicist, he did experiments with cathode rays which led him to discover electrons, with this new information he furthered the model of the Atom. The Plum-pudding model, -
Rutherford
A New Zealand physicist, he became known as the father of nuclear physics. He discovered the nucleus of an atom, Protrons, Alpha particles and Rutherford scattering. -
Bohr
Bohr was a Danish physicist.Bohr developed the Bohr model of the atom which shows that atom have energy levels. -
Erwin Schrödinger and Werner Heisenberg
They invented a new quantum theory of physics. They took the Bohr model one step further, they tried to figure out where the electrons were.This atomic model is known as the quantum mechanical model of the atom. Involves the atomic cloud. -
Chadwick
a British physicist,who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932. He confirmed that the nucleus had all the mass and he discovered an uncharged particle, The Neutron!!!!. He added upon the quantum mechanical model of the atom. Adding neutrons.
