-
JJ Thomson
In 1897, J.J. Thomson discovered the electron by experimenting with a Crookes, or cathode ray, tube. He demonstrated that cathode rays were negatively charged. In addition, he also studied positively charged particles in neon gas. -
Ernest Rutherford
In 1911, although he could not prove that it was positive or negative, he theorized that atoms have their charge concentrated in a very small nucleus, and thereby pioneered the Rutherford model of the atom, through his discovery and interpretation of Rutherford scattering in his gold foil experiment. -
Niels Bohr
In 1913 one of Rutherford's students, Niels Bohr, proposed a model for the hydrogen atom that was consistent with Rutherford's model and yet also explained the spectrum of the hydrogen atom. The Bohr model was based on the following assumptions. -
Electron Cloud Model
Austrian physicist Erwin Schrödinger (1887-1961) developed an “Electron Cloud Model” in 1926. It consisted of a dense nucleus surrounded by a cloud of electrons at various levels in orbitals -
James Chadwick
Sir James Chadwick, CH, FRS (20 October 1891 – 24 July 1974) was an English physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932. In 1941, he wrote the final draft of the MAUD Report, which inspired the U.S. government to begin serious atomic bomb research efforts. He was the head of the British team that worked on the Manhattan Project during the Second World War. He was knighted in England in 1945 for his achievements in physics.
