Give names of atomic models and write about Thomson model.

(N/A) There are four atomic models:
$(1)$ Thomson model of atom.
$(2)$ Rutherford's nuclear model of atom.
$(3)$ Bohr's model of atom (For hydrogen).
$(4)$ Quantum mechanical model of atom.
$J. J. Thomson$,in $1898$,proposed that:
- An atom possesses a spherical shape (radius approximately $10^{-10} \ m$) in which the positive charge is uniformly distributed.
- The electrons are embedded into it in such a manner as to give the most stable electrostatic arrangement.
- According to Thomson,the positive charge is distributed throughout the sphere.
Many different names are given to this model,for example: This model can be visualised as a pudding or watermelon of positive charge with plums or seeds (electrons) embedded into it.
An important feature of this model is that the mass of the atom is assumed to be uniformly distributed over the atom.
Although this model was able to explain the overall neutrality of the atom,it was not consistent with the results of later experiments.
According to Rutherford's $\alpha$-particle scattering experiment,most of the space in an atom is empty,which cannot be explained by the Thomson model.