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Democritis
Democritis was a Greek philosopher who said that matter could not be divided into smaller and smaller pieces. Once you get the smallest piece that is called the atom. -
John Dalton
John Dalton (1766-1844) was an English cehmist who is best known for his atomic theory discover. In this theory he stated that all matter is made of atoms and that atoms are indivisible and indestructible. He also said that all atoms of specific element are identical in mass and properties. He discovered how compound are formed with two or more different kinds of atoms and how chemical reactions is a reaarangement of atoms. -
Dmitri Mendeleev
A Russian Chemist who created the periodic table of elements. -
J.J Thompson
Discovery of the electron by conducting the cathode ray tube experiment and concluded that as cathode rays carry a charge of negative electricity, they are deflected by an electrostatic force. He changed the view of the atom by developing a newer atomic model which suggested that the atom consists of a sphere of positive charge with negatively charged electrons embedded into it. -
Robert Millikan
Robert Millikan discovered the charge of an electron with his oil drop experiment. -
Ernest Rutherford
Ernest Rutherford was a New Zealand born British Chemist and Physicist. Rutherford theorized that atoms have their charge concentrated in a very small nucleus. He conducted the gold foil experiment which lead to the discovery that atoms have a nucleus with protons and neutrons with electrons that orbit the nucelus, therefore creating a new atomic model named the planetary model. -
Neils Bohr
Neils Bohr who was a Danish physicist who refined Rutherfords model by proposing that elecrons orbit the nucleus without losing energy and could only move in fixed orbits of specific energies. -
Erwin Schrodinger
Erwin Schrondinger added to the bohrs model by developing a electron cloud model which is basically a cloud around the nucleus showing where electrons is likely to be found. -
Louis de Broglie
He proposed that electrons could behave as waves and made clear to other scientists that atom's didn't behave like the solar system because electrons don't have regular orbits.
