STRUCTURE OF ATOM
WWW.DOUBTZONE.COM Introduction to Structure of an Atom Atoms Atoms are the building blocks of matter. It is the smallest unit of matter that is composed of three sub-atomic particles: the proton, the neutron, and the electron. Cathode ray experiment J. J. Thomson discovered the existence of electrons. He did this using a cathode ray tube, which is a vacuum-sealed tube with a cathode and anode on one end that created a beam of electrons travelling towards the other end of the tube. The air inside the chamber is subjected to high voltage and electricity flows through the air from the negative electrode to positive electrode. The characteristics of cathode rays (electrons) do not depend upon the material of electrodes and the nature of the gas present in the cathode ray tube. The experiment showed that the atom was not a simple indivisible particle and contained at least one subatomic particle - the electron. Apparatus of the experiment Elect...