Occurrence and Uses of the Commonest Elements

Element Atom % Weight % Element Atom % Weight % 

Inorganic chemistry draws its strength from its great practical utility, and this book presents the subject from the standpoint of applications rather than the customary one of quantum mechanical bonding theory. Since the quintessential subject matter is the properties of the 112 known chemical elements and their compounds, we begin with a consideration of the availability of the commonest elements in the Earth s crust (Table 1.1), hydrosphere (i.e., oceans, lakes, rivers, snowfields, ice caps, and glaciers), and atmosphere, along with brief summary of the production and uses of these elements and their compounds. 

Oxygen occurs as the free element (O2) in the atmosphere (21%), from which it is obtained by fractional distillation of liquid air or by membrane technologies, but far greater amounts axe found in the Earth s crust in 

Silicon is the most important constituent of igneous and many sedimentary rocks, occurring in combination with oxygen in feldspars, micas, quartz, sands and shales. The element is used in electronic devices, while silicon in combination with oxygen as silica and silicates finds application in concrete, bricks, pottery, enamels, glasses, optical fibers for telecommunications, and refractory (high-temperature resistant) materials. 

Aluminum (properly called aluminium, but the former name prevails in North America) is found in combination with Si and O as aluminosilicates in rocks, and as its ore, bauxite. The metal finds use in vehicles, aircraft, packaging, cookware, construction materials, etc., while aluminum salts are used in baking powders, water treatment, and dyeing of textiles. Aluminum oxide is widely used as a refractory and as a support for catalysts. Aluminosilicate catalysts such as zeolites are of key importance in the chemical and petroleum industries. 

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