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370
Democritus
Experiment: none.
Discovery: indivisible particles.
Atomic Model: the universe and all matter obey principles. -
Dalton
Discovery: built on atomic theory
Experiment: various gasses and tests on their reactivity to each other to find different weights of atoms.
Atomic Model: all matter is composed of very small things called atoms. -
William Crookes
Experiment: Crookes tube.
Discovery: discovered thallium and discovered cathode rays. -
Antoine Henri Becquerel
Experiment: created a photographic plate that showed the effect of exposure to radioactivity.
Discovery: radioactivity.
Atomic model: nuclei break down and release these high energy particles called radioactivity. -
JJ Thomson
Experiment: Cathode ray tube experiment.
Discovery: Electron.
Atomic model: plum pudding model of the atom. discovery of the atomic nucleus in order to include the electron in the atomic model. -
Marie Curie
Experiment: mineral pitchblende.
Discovery: radium and polonium. -
R.A. Millikan
Discovery: size of the charge on an atom.
Experiment: oil drop experiment.
Atomic Model: explained the structure of an atom. -
Niels Bohr
Discovery: Energy between atoms is only transmitted through well defined quantities.
Experiment: Oscillating fluid jets to investigate surface tension. -
Ernest Rutherford
Discovery: proper structure of an atom.
Experiment: Gold foil experiment. Bombarded a thin gold foil surrounded with a circular screen coated with zinc sulphide with a beam of alpha particles in vacuum.
Atomic model: The model described the atom as a tiny, dense, positively charged core called a nucleus, in which nearly all the mass is concentrated, around which the light, negative constituents, called electrons, circulate at some distance. -
Erwin Schrodinger
Discovery: Schrodinger came up with a groundbreaking wave equation for electron movements.
Experiment: He took the Bohr model and used mathematical equations to find likelihood of finding an electron in certain positions -
James Chadwick
Discovery: the Neutron in 1932 and in 1941 wrote a final book on the idea which led to government investigation into the atomic bomb
Experiment: Chadwick took the Alpha Source and sent it through beryllium then through paraffin wax to separate protons and neutrons using radiation