Why Metals Corrode

The driving force that causes metals to corrode is a natural consequence of their temporary existence in metallic form. In order to produce metals starting from naturally occurring minerals and ores, it is necessary to provide a certain amount of energy. It is therefore only natural that when these metals are exposed to their environments they would revert back to the original state in which they were found. A typical cycle is illustrated by iron. The primary corrosion product of iron, for example, is Fe(OH)2 (or more likely FeO-nH O), but the action of oxygen and water can yield other products having different colors  

The high reactivity of magnesium and aluminum expressed as energy in Table 2.2 is paralleled by the special efforts that were historically required to transform these metals from their respective ores. The industrial process to produce aluminum metal on a large 

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Sample Description Chemical or Mineral Name Chemical Formula  

Substance found beneath paint on metal surface Alpha quartz SIO  

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