The dissolution of magnesium in strong acids

The rapidly growing demand for magnesium and magnesium-base alloys in the manufacture of aircraft has led to a great amount of research into the corrosion characteristics of these materials. The result of such research has been the development of suitable magnesium alloys and protective coatings to retard corrosion. The standard electrode potential of magnesium lies between -2.35 volts and -2.54 volts at 25⁰C (hydrogen scale). Thus, magnesium lies next to aluminium in the electrochemical series of elements. The atmospheric corrosion of magnesium has been studied under conditions of indoor and outdoor exposure. Under these conditions the initial attack is formation of a hydroxide film which has a tendency to absorb carbon dioxide and moisture from the air. As a pure metal, magnesium is attacked rapidly by hydrochloric, perchloric, sulfuric, and nitric acids. In hydrofluoric acid the metal does not corrode at an appreciable rate. Magnesium metal is rarely, if ever, used in unalloyed conditions for structural purposes. The corrosion rate is retarded by alloying the metal with small quantities of aluminium, manganese, and zinc. The purpose of this present investigation was to study the dissolution of magnesium in strong acids. It was also aimed to investigate whether magnesium metal exhibits uncommon valence characteristics as reported in the literature. The strong acids included hydrochloric, perchloric, and sulfuric acids --Introduction, pages 1-2