Question

Why the charge to mass ratio of anode rays depend on the gas through which it pass ?Why it does not depend upon the protons as they are made up of protons and charge and mass of protons is same for all elements?

Answer 1

Anode rays are produced in the discharged tube when high electrical voltage is applied to the gas which is present in the tube, and its atoms break down into negatively charged particles and positively charged particles. These positive charged particles are anode rays. Thus, anode rays are not emitted from the anode but are produced in the space between the anode and the cathode. The nature of anode rays depends on the gas which is taken in the tube because these rays are produced from them.
Now, different gases have different types of positive rays, which contain particles having different mass and charge. Hence, charge to mass ratio of anode depends on the gas. This ratio is not constant.