State two main postulates of Thomson model of an atom

Thomson's model of an atom is similar to the model of a plum pudding or watermelon. It can be explained with the help of a watermelon. He said that the positive charge in the atom is spread all over like the red edible part of the watermelon. Also, the electrons are embedded in the positively charged sphere like the seeds in the watermelon (as shown in the given figure).

Figure: Explanation of Thomson’s model.

Hence, according to Thomson’s atomic model :

1. An atom consists of a positively charged sphere with electrons embedded in it.
2. The negative and positive charges present inside an atom are equal in magnitude. Therefore, an atom as a whole is electrically neutral.

Thomson’s model of the atom is also known as the plum pudding model.