atomic models

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 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 circula..

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..

(i) Every atom consists of a nucleus containing the entire +ve charge. The whole mass of atom is concentrated at this core. (ii) The size of the nucleus i.e., 10 - 1 5 m is very small compared to the size of the atom (i.e., 10 - 1 0 m). (iii) The atom..

where 'Z' is the nuclear charge, which is equal to atomic number. Although Bohr's model successfully explained the stability and the line spectrum of hydrogen, it had its limitations. They wer..

Atomic Structure..

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

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 energy..

Wave nature of material objects In 1924, de Broglie's suggested that all material objects including an electron have a dual character; they behave as particles as well as waves. The wavelength associated with a particle of mass 'm', moving with velocity 'v' is given by de Broglie's relation as: ..