What are the differences between the old models of an atom and the current model of an atom?

Question

The comparisons between the models of atoms

Answer 1

There is whole bunch of them, to put it mildly. Read a chapter from Ashkroft and Mermin "Solid State Physics". Or, this link for starters: http://en.wikipedia.org/wiki/Rutherford_model

The most famous ones are by Thompson (plum pudding model, outdated), Rutherford (outdated), Bohr (has to postulate that electron doesn't radiate enery as it revolves around the nucleus; explains some phenomena and gives some good estimations, but yes outdated as well), and Heisenberg ("electron clouds" which are probabilities to find an electron at some space interval at some time. You can safely assume this model is current).

Answer 2

This can be pretty deep. The simple answer is that it was thought that an electron orbited the atom's nucleus like a moon orbits a planet, whirling so fast that it creates what is known as an electron shell around it.

What is now believed is that the electron appears and disappears through action on the quantum level, popping in and out of space, instead of whirling around. Where it goes when it disappears, no one knows, but it is assumed it is an alternate dimension, or alternate reality.

In addition, it was thought that atoms were composed of protons, neutrons, and electrons. It is now believed that each of these can be broken down into elementary quantum particles called quarks.

Anything deeper than that, go read some papers from Grad students at MIT.

Answer 3

there are different models, 1st is that it is indivisible, later it is a cloud of positive and negative charges, without a nucleus. Eventually it has a core of neutros and positively charged protons as well as negatively charged electrons in orbit. Though we are never really sure of the exact orbit. The differences in model also explains why conventional current flow is opposite the actual electron flow in electricity, people used to think it's the positive charges that flow.

Answer 4

The older models talked about electron shells that would sort of nest inside of each other. Newer models now talk about "electron clouds" - since scientists aren't sure exactly where the electrons are, the clouds are the mathematically probable paths of the electrons.

Answer 5

old model of atom is given by bohrs's and current by rutherford