Chem - Timeline

400 BC Democritus proposed the atomic theory.

1803 John Dalton said that all things are made up of matter. He also said that atoms are invisible and indestructible.

1906 Marie Curie had her breakthrough on radioactivity.

1911 Ernest Rutherford said that atoms have a small charged nucleus surrounded by largely empty space and are circled by tiny electrons

1910 Robert Millikan discovered the quantity and determination of the charge carried in an electron

1926 Erwin Schrödinger made the quantum mechanical model of the atom

1932 James Chadwick discovered the nutron.

1942 Albert Enstien helped to create the atomic bomb, which ended World War 2 in the Pacific.

1925 Werner Heisenberg developed the “matrix mechanics” formulation now-now for quantum mechanics

1913 Niels Bohr had his breakthrough on the atomic model

1897 J.J. Thomson had his breakthrough on the discovery of the electron

1783 Antoine Lavoisier concluded that water is not an element

1909 Robert Millikan did his oil drop experiment that allowed for the calculation of the mass of the electron and the positively charged atoms

1924 Louis De Broglie discovered the wave nature of electrons and suggested that all matter have wave properties.

1918 Max Planck had his discovery of energy quanta.