Atomic Structure

X-RAYS AND ATOMIC NUMBER: -

            In 1895 W.C Roentgen discovered x-rays It was observed that when cathode rays strike the metal acting as an anode, certain,  kind of highly penetrating radiation is produced. As these radiations or rays were of new kind they were named as X-rays.

            X-rays are radiation of very high frequency. The frequency of the x-rays depends on the material used as an anode. Later on 1913 Mosley was able to show that the frequency of emitted rays increases with the number of positive charge on the nucleus
of target element and that they increase from element to element by  single electron unit.
            “This number of positive charge on the nucleus of an atom of an element is now called as the ATOMIC NUMBER denoted by Z”.
            As each proton has a unit positive charge, the atomic number Z of an element is number of protons contained in the nucleus atom.