How does a Bohr model illustrate electron placement within an atom?
electron travel around the neucleus in different (fixed) energy levels
How does the wave model of electron placement differ from the model of electron postition proposed ny Niels Bohr?
Bohr's model depicts electrons in orbit around the nucleus. the electron cloud model shows orbitals within which an electron most likely is at any given time (the movement of electrons are random, and sometimes they get out of their orbital...i'm not making this up!). the electron cloud model is more accurate because electrons move closer and farther away from the nucleus, while the bohr model shows them at a given radius at all times.
The Bohr model happens to be discovered by Niels Bohr of course and it shows the atom in a version with energy levels where as the electron cloud model shows the nucleus with its neutrons and protons but the electrons are very detailed and are situated within a area around the nucleus. Electrons move so fast that it is impossible to pinpoint their location in a model. Hence the name Electron Cloud
The Thomson atomic model is referred to as the blueberry muffin or plum pudding model. The name is derived from the visual interpretation that an atom is a circle with electrons arranged non-randomly in rotating rings. The electron placement is said to resemble the raisins in plum pudding or the berries in a muffin.
Sommerfield's model is a semi quantum-mechanics, a classical free electron model. However, it differs from the Drude's model since it is incorporate in a quantum mechanics idea such that : - Only discrete energy levels are allowed for the electron. - Together with the Pauli Exclussion Principle and Fermi-Dirac statistic which deal with the probability of occupancy of the energy states by electron. - The density of available states for the electron occupancy.