Question

High purity copper metal is obtained by:
A.Carbon reduction
B.Hydrogen reduction
C.Electrolytic reduction
D.Thermite reduction

Answer 1

To solve this question, you must recall various methods for refining of copper metal and the products obtained as a result. Methods used for the refining of a metal are chosen depending on the physical and chemical properties of the metal.

Complete step by step answer:
Commonly, the process of smelting is used for the extraction of copper from its sulphide ores. In the process of extraction of copper, first we purify the copper matte. Copper matte is a combination of iron sulphide and copper sulphide which is extracted and formed prior to the final step. It generally contains around $30 - 70\%$ copper in the form of copper sulphide and the remaining part is iron sulphide. The copper matte is taken in the molten state and air is blown through it at a very high temperature. The Sulphur present in the copper sulphide is removed as Sulphur dioxide.
The copper obtained in this reaction is known as blister copper. The blister copper obtained is purified further by electrolysis. The anode is made up of blister copper and the cathode is made up of pure sheets of copper coated with graphite. On electrolysis, the impurities fall to the bottom and we get deposited on the cathode $100\%$ pure copper.
Thus, we obtain high purity copper metal using the method of electrolytic reduction.

Thus, the correct answer is C.

Note:
The above process of formation of blister copper is known as Bessemerization process. . Blister copper is the second most pure form of copper next to the electrically refined which is $100\%$ pure. It is around $98\%$ pure and contains impurities of iron mainly and in small amounts, those of arsenic, zinc, lead, gold and silver.