1. J.J. Thomson’s theory proposed that the atom has positively charged part like the red part of the watermelon and in it are embedded, like the seeds, negatively charged particles which he called electrons.
2. According to this theory as the positive and negative charges are equal, the atom as a whole does not have any resultant charge.
3. Thomson’s greatest contribution was to prove by experimentation the existence of the negatively charged particles or electrons in an atom.
