Metals

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An ore is any mineral from which a metal can be extracted easily and economically. A mineral is any naturally occurring metal or compound found in earth's crust. The key difference is that ores are su…

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1. Hydraulic washing/Levigation - Used when ore is denser than gangue (oxide ores) 2. Froth flotation - Used when ore is less dense than gangue (sulphide ores) 3. Magnetic separation - Used when ore o…

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Calcination is heating concentrated ore in limited quantities or absence of air at a temperature below the melting point. It converts metal carbonates or hydroxides to their oxides. Example: ZnCO₃(s) …

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Roasting is heating concentrated ore at a temperature below the melting point in the presence of air. It converts metal sulphides to their oxides. Example: 2ZnS(s) + 3O₂(g) →heat→ 2ZnO(s) + 2SO₂(g) An…

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1. Highly reactive metals (K, Na, Ca, Mg, Al) - Extracted by electrolysis 2. Moderately reactive metals (Zn, Fe, Sn, Pb) - Extracted by reduction using carbon/coke 3. Less reactive metals (Cu, Hg, Ag,…

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Fe₂O₃(s) + 3CO(g) → 2Fe(l) + 3CO₂(g) This reaction occurs in the blast furnace where carbon monoxide acts as the reducing agent to convert iron oxide to metallic iron.

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Limestone acts as flux to remove acidic impurities (gangue) like silica. 1. CaCO₃(s) →heat→ CaO(s) + CO₂(g) (limestone decomposes) 2. CaO(s) + SiO₂(s) → CaSiO₃(l) (flux + gangue → slag) The slag float…

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• Pig iron: 4% carbon, contains impurities, brittle • Cast iron: >2% carbon, can be cast into shapes • Wrought iron: 0.02-0.05% carbon, pure, malleable • Steel: 0.05-1.5% carbon, strong and versatile …