pictures of atomic models

The atom of an element consists of a small, positively charged nucleus in the centre, which carries almost the entire mass of the atom. The electrons are revolving around the nucleus at high speed. The number of electrons in an atom is equal to the number of protons..

The wave character of an electron and uncertainty in its position and momentum gave a serious blow to Bohr's model of an atom. According to Bohr, the electrons revolve around the nucleus in certain well-defined circular orbits. But the idea of uncertainty in position and velocit..

Atomic Models..

'Raisin Pudding' Model - Thomson's model of atom : J. J Thomson the discoverer of the electron believed that the atom is a uniform sphere of positive charge with electrons (raisins) embedded in i..

. In 1793, he left for Manchester to teach physics and chemistry in a college. In 1801, he observed and discovered the law of expansion of gases on heating. He also enunciated the law of partial pressures and found methods of determining vapour pressure of gases. He invented the dew point hygromete..

Quantum Mechanical Model of the Atom - Two new theories came to substantially modify Bohr's Atomic model. They a..

Bohr's Model of an Atom - Rutherford's model had a major drawback. It could not explain why ultimately electrons did not fall into the nucleus by taking a spiral path. This was in concurrence with the electromagnetic theory that states 'if a charged particle undergoes ..

Rutherford proposed that electrons revolve at high speed in circular orbits around the positively charged nucleus. But according to the electromagnetic theory, if a charged particle were accelerated around another charged particle then there would be a continuous radiation of energy. The loss of ..

Rutherford's model had a major drawback. It could not explain why ultimately electrons did not fall into the nucleus by taking a spiral path. This was in concurrence with the electromagnetic theory that states 'if a charged particle undergoes accelerated motion then it must radiate ..

In 1913, Neils Bohr proposed a model of an atom based on the Planck's quantum theory of radiation. The basic postulates of Bohr's theory are: An atom consists of a small, heavily positively charged nucleus around which electrons revolve in definite circular paths ca..