Question

Hoopes’ process used for:

• A. Extraction of copper
• B. Concentration of lead ore
• C. Refining of aluminium
• D. Refining of titanium

Hint:

Hoopes’ process refines aluminium electrolytically using a 3-layered cell, producing 99.99% pure aluminium.

Answer 1

The Correct Option is C

Step 1: What is Hoopes' Process?
Hoopes' process is an electrolytic refining method used for the purification of aluminium. It was developed by William Hoopes and is specifically used to obtain ultra-pure aluminium (about 99.99%). Step 2: Working Principle
The setup involves: - A three-layered cell: - Top layer: Pure aluminium (cathode), - Middle layer: Electrolyte (a mixture of molten salts like BaCl\(_2\), NaCl, and AlF\(_3\)), - Bottom layer: Impure aluminium (anode). When current is passed: - Aluminium ions from the impure bottom layer migrate through the electrolyte and deposit as pure aluminium in the top layer. Step 3: Elimination of Incorrect Options
- Copper: Refined using the electrolytic method, not Hoopes’.
- Lead ore: Concentration uses methods like froth flotation.
- Titanium: Refined using the Kroll process, not Hoopes’. Conclusion: Hoopes’ process is used exclusively for the refining of aluminium.