1) Occurrence of metals and non metals :- •Out of the 92 naturally occuringelements 70 are metals and about 22 are nonmetals. Some elements show properties of both metals and non metals. They are called metalloids. •Only some metals like gold, silver, platinum etc are found in the free state. Most metals are found in the combined states as oxides, sulphides, carbonates, silicates etc. • Some non metals are found in the free state like helium, neon, argon etc. and some are found in free and combined states like sulphur, phosphorus etc. 2) Metallurgy :- •Metallurgy:-is science of extraction of metals from their ores and their purification. •Minerals:-are naturally occuringsubstances containing one or more elements or their compounds. •Ore:-is a mineral from which one or more metals can be extracted profitably. •Metallurgical processes:-consists of three main steps. They are :-i) Concentration of the ore ii) Reduction iii) Refining •Concentration of the ore:-is the remo
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