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Which of the following statements about metallurgical processes is/are INCORRECT? (A) In the Bayer process for leaching of aluminium ore, a small amount of freshly prepared hydrated Al2O3 is added as a seed to induce precipitation. (B) Wrought iron is the purest commercial form of iron and is prepared from cast iron by oxidizing impurities in a furnace lined with haematite. (C) Copper matte consists primarily of Cu2O with a smaller amount of FeS. (D) Extraction of zinc from zinc blende involves calcination followed by reduction with carbon.

1. (A) only
2. (B) only
3. (C) only
4. (D) only

Correct answer: (C) only

Solution

In copper metallurgy, after roasting, the matte that forms consists mainly of Cu2S (copper(I) sulfide) and FeS (iron sulfide), NOT Cu2O. Statement C is therefore incorrect. Statements A, B, and D accurately describe their respective processes.

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