Ores

Some metals are found as elements in the Earth's crust. This means the metal is not combined with other elements. Metals found as elements are very unreactive metals such as gold. This means lumps of gold can sometimes be found.



Extracting Metals
Most metals are found as part of a compound. For example, iron is found as iron oxide. The metal compounds are mixed up with other compounds in rocks. If a rock has enough of the metal compund in to make it worth while to extract it, the rock is called an ore. Metals are extracted from the compunds found in ores. The method used to extract a metal depends on how reactive the metal is.

Iron and aluminium
metals such as iron are extracted from their compounds by heating the ores with carbon. Iron oxide + carbon = iron + carbon dioxide

More reactive metalssuch as aluminium are extracted by melting the ore and then carrying out electrolysis. Electrolysis decomposes aluminium oxide. Aluminium oxide = aluminium + oxygen.