(a) What are cathode rays? What is the nature of charge on cathode rays?(b) Explain how, cathode rays are formed from the gas taken in the discharge tube.(c) What conclusion is obtained from the fact that all the gases from cathode rays?

(a) In an experiment, Thompson passed electricity at high voltage through a gas, in a discharge tube. Stream of minute particles was emitted by the cathode. This stream of particles was called cathode ray as it was emitted from the cathode.

Nature of cathode rays:  Cathode rays consist of small negatively charged particles called electrons.

(b) Formation of cathode rays: When electricity at high voltage is passed through a gas taken in a discharge tube, streams of minute particles are given out by the cathode. This happens because the gas taken in the discharge tube consists of atoms, and all the atoms contain electrons. When high electrical voltage is passed, the electrical energy excites and pushes out some of the electrons from the atoms of the gas. These fast-moving electrons form the cathode rays.

(c) The formation of cathode rays shows that one of the subatomic particles present in all atoms is the negatively charged electrons.