Introduction to J.J.Thomson atomic theory:-
Thomson discovered the electron in the year 1897. His work put forward a new theory, that atom was made up of small particles.Thus he discovered the electrons. He proved his theory using the cathode ray tube.
Scientists had already done many experiments to find the structure of the atom. They passed an electric current through a vacuum tube. They saw a light glowing inside the tube. It travelled in a straight line. They could not explain the phenomenon. Thomson did more experiments on the cathode tube. He placed two electric plates on its path. One was positively charged. The other was negatively charged. The glowing light bent towards the positively charged plate.and found that the glowing materials bent towards the positively charged plate. He found out that the glowing light were smaller particles. They were smaller than the atom. Thus Thomson found the particle called electron. Thus J.J.Thomson's atomic theory was found.
Thomson suggested that the electrons came out ofthe trace gas that was inside the cathode tube. Thus a new theory that atoms were made of tiny particles surfaced.
Thomson discovered the electrons and it was proved that atoms were made up of protons, electrons and neutrons. Thus
Thomson proved that the atom was divisible. Since the atom was neutral, Thomson suggested that the negatively charged electron equalled the positively charged proton and neutrons had no charges.Thomson suggested to consider the atom as a sphere. It has positively charged particles The positively chargedparticles is surrounded by the negatively charged electons.The electrons were placed there due to electrostatic forces.