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John Dalton
Contribution to the study of the atom: He proposed the Atomic Theory in 1803 which stated that (1) all matter was composed of small indivisible particles termed atoms, (2) atoms of a given element possess unique characteristics and weight.
Additional Science Information: He was a meteorologist and proposed of his ideas about the atmosphere. -
JJ Thomson
Contribution to the study of the atom: Thomson determined that all matter is made up of tiny particles that are much smaller than atoms. He originally called these particles 'corpuscles,' although they are now called electrons.
Additional Information: Thomson began studying positively charged ions. In doing so, he discovered that neon was composed of two different kinds of atoms, and proved the existe -
Hantaro Nagaoka
Hantaro Nagoka made his contribution to the atom in 1904. Nagaoka developed a planetary model of the atom. The model looked like Saturn, the electrons were the rings and the nucleus was the planet.
He also was a professor of physics at the University of Tokyo. -
Ernest Rutherford
Ernest Rutherford created his atomic theory in 1911 describing the atom as having a central positive nucleus surrounded by negative orbiting electrons.
He also won The Nobel Prize in Chemistry in 1908. -
Niels Bohr
Bohr’s atomic model was created in 1913 and shows the atom as a small, positively charged nucleus surrounded by orbiting electrons.
He won a Nobel Prize in 1922. Bohr was the first to discover that electrons travel in separate orbits around the nucleus. -
G.N. Lewis
His theory was that there are eight electrons in the outer orbit of an atom. This was developed in 1916.
He was the Dean of the college of Chemistry at Berkeley, where he spent the rest of his life. -
James Chadwick
James Chadwick proved the existence of neutrons in 1932.
He was awarded a Nobel Prize for Physics in 1935 for his discovery.
