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Dalton Solid Sphere Model
The solid sphere model proposed by John Dalton stated that atoms consisted of negative charges embedded in a solid continuum of positive charge. The magnitude of the embedded negative charge would cancel the positive charge of the continuum, rendering the entire atom neutral. -
Thompson Plum Pudding Model
J. J. Thomson 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 balance the electrons’ negative charges, like negatively charged “plums” surrounded by positively charged “pudding”. -
Rutherford Atomic Model
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 electrons, circulate at some distance, much like planets revolving around the Sun. -
Bohr: The Bohr (Planetary) Model
In 1913 Bohr proposed his quantize shell model of the atom to explain how electrons can have stable orbits around the nucleus. The motion of the electrons in the Rutherford model was unstable because, according to classical mechanics and electromagnetic theory, any charged particle moving on a curved path emits electromagnetic radiation; thus, the electrons would lose energy and spiral into the nucleus. -
Schrodinger: Quantum Mechanics Model
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 -
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