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500 BCE
Hindu Philosophers
Discuss atoms as ultimate pieces of elements earth, air , water , and fire. atoms are round and differ in properties such as color , flavor and oder -
Dalton
The Solid Sphere Model was the first atomic model and was developed by John Dalton in the early 19th century. He hypothesized that an atom is a solid sphere that could not be divided into smaller particles. He came up with his theory as a result of his research into gases. -
Thompson
J. J. Thomson, who discovered the electron in 1897, proposed the plum pudding model of the atom in 1904 before the discovery of the atomic nucleus in order to include the electron in the atomic model. In Thomson's model, the atom is composed of electrons surrounded by a soup of positive charge to bal -
Rutherford
Rutherford atomic model, also called nuclear atom or planetary model of the atom description of the structure of atoms proposed (1 by the New Zealand born physicist Ernest Rutherford. The model described the atom as a tiny, dense positively charged core called a nucleus, in which nearly all the mass is concentrated, around which the light, negative constituents, called elctrons, circulate at some distance, much like planets revolving around the Sun. -
Bohrs atom model
describes a dense postivlty charged nucleus containing nearly all the atoms mass. surrounded by the electrons traveling in specific aloud orbits -
Schrodinger
In 1926 Erwin Schroodinger an Austrian physicist, took the Bohr atom model one step further. Schrodinger used mathematical equations to describe the likelihood of finding an electron in a certain position. This atomic model is known as the quantum mechanical model of the atom. -
Today
Electrons travel not in orbits but exist as clouds of electric charge within orbitals the deffine regions of space with a high probabilty of containing electron