According to the j.j Thomson's model of an atom, the electrons are embedded  all over in the positive charged  spheres. but the experiments done by  other scientist showed that protons are present only I the center of the atom and electrons are distributed around it.
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Limitations of Thomson's model of an atom :-
1.It could not explain the result of scattering experiment performed by Rutherford.
2.It does not have any experimental evidence in its support.
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