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Democritus (460-370 BC)
CitationHe was known for naming particles atoms. He believed that they were infinite in number, always moving, could combine with other atoms, and each subastance had atoms of unique shape and size. -
John Dalton (1766-1844)
Dalton believed that all matter is made of atoms, atoms are indivible and indestructable, all atoms of a given element are identical in mass and properties, compounds are formed by a combination of two ro mor different kinds of atoms -
J.J Thomson (1856-1940)
J.J Thomson discored the electron. He discovered the electron in 1897. He won the Nobel Prize in 1906. He experimented with a Cathode Ray Tube. He proposed a similar model to a chocolate chip cookie. -
Ernest Rutherford (1871-1937)
He won the Nobel Prize in chemistry in 1908. He discovered the positve charge was located in the center or nucleus of the atom and that most of the atom was empty space. -
Neils Bohr (1885-1962)
He won the Nobel Prize in 1922. He proposed that electrons orbit the nucleus without losing energy, could move only in fixed orbits of specific energies, and that electrons with low energy would orbit closer to the nucleus while electrons with high energy orbit further from the nucleus. -
James Chadwick (1891-1974)
He won the Nobel Prize in for physics in 1935. He discovered the existence of nuetrons.
