ABSTRACT
Magnesium is widely distributed in nature in a variety of compounds. It is estimated that magnesium forms about 2.5% of the crust of the Earth. The circumstances of its discovery have been previously reported. Ordinary magnesium has an atomic weight of 24.312. Its atomic number is 12; its valence, 2. Its isotopic composition is as follows: 24 (77.4%), 25 (11.5%), and 26 (11.1%). The nucleus of the magnesium atom contains 12 neutrons and 12 protons. The binding energies of the complex ions are determined above all by the relative sizes of their atoms; the smaller the relative size of the atom, the greater the binding energies and the greater the tendency to form complex compounds. While barium and strontium show no tendency to complex formation, this tendency is shown increasingly by calcium and magnesium.
