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Difficulty: MediumGeneral Principles of Metallurgy and Metal Extraction

Match each metallurgical process or extraction stage on the left with its corresponding chemical principle or operational method on the right.

  • Concentration of low-grade sulfide oresFroth flotation using oil collectors and agitation to float hydrophobic ore particles
  • Extraction of highly electropositive metals (e.g., Sodium, Aluminium)Electrolysis of fused (molten) salts or oxides due to strong chemical bonding
  • Reduction of haematite (Fe2O3Fe_2O_3) in a blast furnaceChemical reduction by carbon monoxide gas (COCO) at high temperatures
  • Refining of crude blister copperElectrolytic dissolution of impure anode and deposition of pure metal on cathode

Answer

Concentration of low-grade sulfide ores matches Froth flotation using oil collectors; Extraction of highly electropositive metals matches Electrolysis of fused salts; Reduction of haematite matches Chemical reduction by carbon monoxide gas; Refining of crude blister copper matches Electrolytic dissolution of impure anode and deposition of pure metal on cathode.
The paired principles directly correspond to standard industrial metallurgy: froth flotation uses oil wettability to concentrate sulfide ores; fused salt electrolysis extracts top-series electropositive metals; carbon monoxide reduces iron oxide in the blast furnace; and electro-refining purifies crude metal using crude anode oxidation and pure cathode deposition.

Step-by-Step Solution

1
Determine the physical concentration technique suitable for sulfide minerals.
Sulfide ores like galena and chalcopyrite selectively attach to air bubbles created by oil collectors and froth up, separating from waste gangue.
Difference in surface wettability between sulfide ore and siliceous gangue.
2
Evaluate the extraction strategy based on the reactivity series of metals.
Metals positioned near the top of the reactivity series (AlAl, NaNa, CaCa) require electrical energy for reduction because carbon cannot displace them from their oxides.
High electropositivity means these metals have higher affinity for oxygen than carbon has.
3
Identify the primary chemical reducing agent in the blast furnace.
Coke burns to form CO2CO_2, which reacts further with coke to give COCO. COCO gas then reduces Fe2O3Fe_2O_3 step-by-step to molten iron.
COCO is a effective gaseous reducing agent that penetrates porous ore charges.
4
Analyze the electrolytic purification mechanism for crude metals.
Impurities stay in solution or form anode sludge while metal ions migrate and plate onto the cathode as pure copper metal.
Anodic oxidation releases Cu2+Cu^{2+} ions while cathode reduction ensures selective plating of pure copper.

Key Concept

General Principles of Metallurgy and Metal Extraction
Estimated Time:1m 30s
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General Principles of Metallurgy and Metal Extraction

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