ABSTRACT
The nuclear constitution of the atom was thus very strongly supported by the experiments on scattering of a-rays. The importance of the atomic number in fixing the properties of an atom was shown by the remarkable work of Moseley on the X-ray spectra of the elements. Charge on the Nucleus: The question whether the atomic number of an element is the actual measure of its nuclear charge is a matter of such fundamental importance that all methods of attack should be followed. Since the atom is electrically neutral, the number of external electrons surrounding the nucleus must be equal to the number of units of resultant charge on the nucleus. It is necessary to emphasise the great importance of the nuclear charge in fixing the physical and chemical properties of an element. The amount of deflexion of charged atoms in a magnetic field perpendicular to the direction of flight is proportional to e/mu.
