-
British chemist John Dalton concluded that each element is made of atoms that are all alike. He also thought that different elements have atoms of different mass. Dalton imagined atoms as tiny, solid balls.
-
British Scientist J.J. Thompson discovered the electron. He later proposed a new model, suggesting that an atom is a positively charged sphere with electrons embedded in it. Like a muffin with blue berries in it.
-
Japanes Physicist Hantaro Nagaoka proposed a model of the atom that looks like a sphere with things swerling around it like planets.
-
British physicist Ernest Rutherford concluded that the atom is mostly empty space. Electrons spin around it.
-
Danish Physicist Niels Bohr proposed a model that showed electrons moving i certain layers and shells around the nucleus.
-
British Physicist James Chadwick discovered the neutron. The existence of neutrons explained why atoms weighed more than there total mass of protons and electrons.
-
The cuurrent atomic model results from work done from the 1920's tot he present day.
