10th Class Science Metals and Non-metals / धातु और अधातु Extraction of Metals

       Extraction of Metals

Most of the metals occur in the earth's crust in the combined state. It is because they are reactive and combine with elements like oxygen, carbon, sulphur etc. Noble metals like gold, platinum etc. exist in free state as they are very less reactive. Minerals are the compounds or the combined form in which a metal occurs in the earth's crust. Ores are those minerals from which metals can be extracted conveniently and profitably. All ores are minerals, but all minerals are not ores

          Some Common Ores  

Sr.No.	Elements	Ores	Formula
1.	Iron	Haematite
2.	Iron	Magnetite
3.	Aluminium	Bauxite
4.	Tin	Cassiterite
5.	Zinc	Calamine
6.	Mercury	Cinnabar
7.	Lead	Galena
8.	Zinc	Zinc blende
9.	Copper	Copper Pyrite

          Gangue

The unwanted impurities like sand, mud, stones etc present in the ore is called gangue or matrix.

• Flux : It is the substance added to the ore to remove gangue.

Slag : Flux combines with the infusible impurities to convert them into a fusible substance called slag.