Question

Match the processes in Column I with the corresponding applications in Column II.
Column I
(P) Fused salt electrolysis
(Q) Carbothermal reduction
(R) Oxidation-refining
(S) Matte converting
Column II
(1) Ironmaking
(2) Aluminium extraction
(3) Copper extraction
(4) Steelmaking

• A. P – 2, Q – 1, R – 4, S – 3
• B. P – 4, Q – 3, R – 2, S – 1
• C. P – 3, Q – 1, R – 4, S – 2
• D. P – 2, Q – 4, R – 1, S – 3

Hint:

Associate key terms with metals: - {Aluminium} \(⇒\) Electrolysis (Hall-Héroult) - {Iron} \(⇒\) Carbothermal Reduction (Blast Furnace) - {Steel} \(⇒\) Oxidation (BOF, EAF) - {Copper} \(⇒\) Matte, Converting

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
This question requires knowledge of the primary processes used in the extraction and refining of common metals. Each process is suited for a particular type of metal or stage of production.
Step 2: Detailed Matching:
- (P) Fused salt electrolysis: This is an electrolytic process used for highly reactive metals that cannot be reduced from their ores by common reducing agents like carbon. The most prominent industrial application is the Hall-Héroult process for the extraction of aluminium from alumina (Al\(_2\)O\(_3\)) dissolved in molten cryolite. P matches with 2.
- (Q) Carbothermal reduction: This involves using carbon (usually as coke) as a reducing agent at high temperatures to reduce metal oxides to metal. The classic and largest-scale example of this is in a blast furnace for ironmaking, where iron oxides are reduced by carbon and carbon monoxide. Q matches with 1.
- (R) Oxidation-refining: This is a refining process where impurities are removed from a molten metal by selectively oxidizing them. The impurities form oxides that either enter a slag phase or leave as a gas. This is the fundamental principle of steelmaking, where excess carbon and other impurities (like silicon, manganese) are removed from molten iron by blowing oxygen through it. R matches with 4.
- (S) Matte converting: "Matte" is a molten mixture of metal sulfides, typically produced during the smelting of non-ferrous sulfide ores like those of copper and nickel. The process of "converting" involves blowing air or oxygen-enriched air through the molten matte to oxidize the iron and sulfur. The iron sulfide is converted to iron oxide (which is slagged off), and the copper sulfide is reduced to blister copper. This is a key step in copper extraction. S matches with 3.
Step 3: Compiling the Matches:
The correct pairings are:
- P \(⇒\) 2 (Aluminium extraction)
- Q \(⇒\) 1 (Ironmaking)
- R \(⇒\) 4 (Steelmaking)
- S \(⇒\) 3 (Copper extraction)
This corresponds to the sequence P-2, Q-1, R-4, S-3.
Step 4: Why This is Correct:
This sequence matches option (A). Each pairing represents a standard, fundamental process in the metallurgy of the respective metal.