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Metallurgy questions in JEE fall into predictable categories. Here is the optimal approach for each.
Ellingham diagram questions: Remember the hierarchy — lower line reduces upper line's oxide. Carbon becomes better at high T (negative slope). Al can reduce Cr2O3, Fe2O3, Mn3O4 but NOT MgO, CaO. If asked "why can't carbon reduce Al2O3?" — answer with Ellingham diagram (C line never goes below Al2O3 line).
Concentration method questions: Match ore type to method — sulphides use froth flotation, oxides use gravity/magnetic, bauxite uses Bayer's leaching, gold uses cyanide leaching.
Blast furnace questions: Know the four zones and their specific reactions and temperatures. CO is the actual reducing agent (not C directly). Stepwise reduction: Fe2O3 -> Fe3O4 -> FeO -> Fe.
Numerical questions: Common calculations involve stoichiometry of reduction reactions, Faraday's laws for electrolysis (Al3+ needs 3F per mole), and mass calculations for thermite reactions.
Common traps: (1) Pine oil is a collector, not a frother. (2) NaCN depresses ZnS, does not activate it. (3) Pig iron has MORE carbon than steel. (4) The Mond process is for Ni only, Van Arkel for Zr/Ti.