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Democritus
Democritus suggested the first theory of atoms, saying all things were "composed of minute, invisible, indestructible particles of pure matter which move about eternally in infinite empty." -
John Dalton
Dalton was a British schoolmaster and chemist. He first made inferences in the 19th century about how atoms bond together. He made up the "Dalton Atomic Theory" which was made up of 5 different theorys. -
William Crookes
Crookes invented the Crookes tube in the early 1870's. He noticed that as you removed gas from a tube, a glow would appear if you place a high voltage across it. He noticed that a shadow would form if something was placed in the tube, so he believed some new kind of light was being produced. He called these cathode rays. -
Dmitri Mendeleev
Mendeleev was a Russian chemist and inventor. He came up with his own Periodic Law and came up with the Periodic Table of Elements, -
Henry Moseley
Moseley was an English physicist. He justified physical laws from previous empirical and chemical concept of the atomic number. -
J.J. Thompson
Thompson discovered the electron. Thompson created a tube that had a positively charged anode on one side and a negatively charged cathode on the other side.He then figured out electrons were present in atoms. -
Ernest Rutherford
Rutherford did an experiment where he put hydrogen atoms between thin gold foil. and the results being revolutionary, they went straight through the foil. -
Niels Bohr
Bohr had the "Bohr Theory of the Atom", which emphazised the idea that there were electrons around the nucleus. -
Erwin Schrödinger
Schrödinger viewed electrons as clouds and introduced "wave mechanics" as a mathematical model of the atom. He thought of the movement of an electron in an atom as a wave.
