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Democritus atomic model
This was Democritus’ atomic model. It was simply a round sphere with no electrons, protons, or neutrons. Democritus created the first atomic model. His contribution helped people with understanding the idea of an atom, and helped other scientists further look into the science of the atom and its generic makeup. -
Dalton's atomic model
Dalton stated his theory in a lecture to the Royal Institution in 1803. The theory proposed a number of basic ideas: All matter is composed of atoms
Atoms cannot be made or destroyed
All atoms of the same element are identical
Different elements have different types of atoms
Chemical reactions occur when atoms are rearranged
Compounds are formed from atoms of the con -
J. Jonah Jameson Thomson atomic model
J.J. Thomson discovered electrons and noticed that an atom can be divided. Also, he concluded atoms are made of positive cores and negatively charged particles within it. He developed the Plum Pudding Model before the atomic nucleus was discovered. This model shows that the electrons are surrounded by a "pudding" of positive charges to balance the negative charges. Today, J.J. Thomson's discoveries have helped people to have a better understanding of the atom and its generic makeup. -
Rutherford atomic model
Rutherford overturned Thomson's model in 1911 with his well-known gold foil experiment in which he demonstrated that the atom has a tiny nucleus. Rutherford presented his own physical model for subatomic structure, as an interpretation for the unexpected experimental results. In it, the atom is made up of a central charge surrounded by a cloud of orbiting electrons. -
Bohr model
He suggested that electrons could only have certain classical motions:
1) Electrons in atoms orbit the nucleus.
2) The electrons can only orbit stably, without radiating, in certain orbits at a certain set of distances from the nucleus also called energy shells or energy levels.
3) Electrons can only gain and lose energy by jumping from one allowed orbit to another. -
Schrodinger and Heisenberg model
Erwin Schrödinger built upon the thoughts of Bohr yet took them in a new direction. He developed the probability function for the Hydrogen atom (and a few others). The probability function basically describes a cloud-like region where the electron is likely to be found. It can not say with any certainty, where the electron actually is at any point in time, yet can describe where it ought to be.
