Isotopes: Their Number and Classification

Abstract

ONE of the most remarkable characteristics of atoms is their predilection for the number 2 or for even numbers. The nuclei of atoms are now considered to be built up from hydrogen nuclei, which may be called positive electrons or protons. Suppose these to be P in number. Combined with these are N negative electrons. Since these N negative electrons may for most purposes be considered to neutralise the charge of N protons, the net positive charge on the nucleus is equal to P–N or M, the Moseley or atomic number. Now it is most remarkable that in about 97–98 per cent, of all atoms N is even; in 90–95 per cent. P is even; and M or P–N is also even in 89 per cent, of the atoms in the surface of the earth and in 98 per cent, of the atoms in thie meteorities.