Page 2 - 3. LESSON NOTES-(CONCEPT OF CATHODE AND ANODE RAYS)
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Electrons


                     Electrons are the negatively charged sub-atomic particles of an atom.
                     The mass of an electron is considered to be negligible, and its charge is -1.
                                                     –
                     The symbol for an electron is e
                     Electrons are extremely small.
                     They are found outside the nucleus.




               Anode or Canal Rays and discovery of protons: By E. Goldstein


               The pressure in the discharge tube is decreased, it was observed that in addition to cathode
               rays, a new kind of rays are also found which came through the perforations (holes) of the
               perforated cathode. These rays travelled in opposite direction of the cathode rays and passed
               through the holes of the cathode and struck the other end of the discharge tube. When these
               radiations struck the end of the tube P, the fluorescent radiations were also produced These rays
               were called canal rays because they are passed through the holes or canals in the perforated
               cathode These were also called anode rays because they move from the anode. It was found
               that the anode rays consist of positively charged particles. Therefore, these rays were also called
               positive rays.






















               Properties of Anode Rays


                     Anode rays travel in straight lines_
                     Anode rays consist of material particles.
                     Anode rays are deflected by electric field towards negatively charged plate. This
                       indicates that they are positively charged
                     Anode rays are deflected by magnetic field the direction of deflection indicates that
                       they are positively charged.
                     Anode rays from different gases are different.

                   When Hydrogen gas was taken in the discharge tube it was found that the anode rays
                   consist of positively charged particles called Protons.


                   Properties of protons:


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