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John Dalton's Atomic Theory
Dalton's theory was that all matter is made of atoms. Atoms are indivisible and indestructible. All atoms of a given element are identical in mass and properties. Compounds are formed by a combination of two or more different kinds of atoms. A chemical reaction is a rearrangement of atoms. Atoms can be neither created nor destroyed. -
Thompson's Atomic Theory
Thompson's theory proposed a model of atom which is known as plum pudding model or Christmas pudding or chocolate chip cookie model. -
Rutherford's Atomic Theory
Ernest Rutherford presented a paper to the Manchester Literary and Philosophical Society accurately describing the structure of the atom. Based on an experiment he had performed - with totally unexpected results - he realized that the atom must have almost all of its mass concentrated at its center, in a nucleus, with the vast majority of the atom consisting chiefly of empty space. -
Bohr's Atomic Theory
Niels Bohr refined Rutherford's model in 1913 by proposing that electrons. orbit the nucleus without losing energy, and could move only in fixed orbits of specific energies. Electrons with low energy would orbit closer to the nucleus while electrons with high energy orbit further from the nucleus. -
Chadwick's Atomic Theory
Chadwick made a fundamental discovery in the doorman of nuclear science. He proved the existence of neutrons. -
Democritus's Atomic Theory
His theory said that matter could not be divided into smaller and smaller pieces forever, eventually the smallest possible piece would be obtained. This piece would be indivisible. He named the smallest piece of matter “atomos,” meaning “not to be cut.”
