Atomic Models

An atomic model is a theory trying to explain the structure of the atom.

When the exact structure of the atom remained quite unknown, models were proposed based on experimental evidence of the properties of matter.

Such models would be purely theoretical constructs. However, they should be able to explain the basic properties of matter.

For example , when the electron was first discover , then JJ Thompson is proposed propose the plum cake model in which he take into consideration the two main point –

1) From the CRT experiments, it was clear that all matter had those electrons within then thus it would be logical to suppose that electrons were a part of atoms.

2) In order to explain the charge neutrality, he supposed that the sphere in which electrons are embedded is positively charged.

In his model, he took the electrons embedded into the positive sphere because he found that these electrons (not some positively charged particle) were emitted by a vast range of marerials.

Further , when Lord Rutherford discover that the positive charge and most of the mass was concentrate in a small region call the nucleus , the propose his model base on what evidence was available at that time on property of atom .

It was soon realize that the model was flawed and soon Bohr put up his model in which he used Quantum concept of Planck and Einstein to explain stability of matter and the Hydrogen spectrum .

And they process continued when Sommerfeld proposed his model.

These models were used to explain and hence to understand properties of matter.

Only when the idea of electron as particle in atom was introduce , attempt were made to understand chemical bonding and other physical and chemical property .

As of now , the electron cloud model is is which incorporate the principle of quantum mechanic is the most successful . From the concept of orbital , one is explains explain molecular structure , chemical bonding , hybridization etc and also thing like spectrum of various material .

That is ‘s ‘s why the atomic model is useful .