Question

Refining of silver is done by:
A. liquidation
B. poling
C. cupellation
D. van Arkel method

Answer 1

Hint: Refining of silver is done by the process that works on the principle that noble metals doesn’t undergo oxidation reaction and they are chemically unreactive.

Complete Solution :
- As we know that cupellation is a refining process, which is used when metals are present under high pressure. It is found that when the noble gases are exposed to the high temperature. It is also found that the other metals, impurities react to form compounds or slag.
- It is found that in small scale cupellation, cupel is flat porous dish, it is used that has an inverted cone shape. To separate silver, alloy is melted at high temperature in an oxidising environment.
- The various impurities like copper, unwanted metals undergo oxidation. It is also found that cupellation is used for testing fresh metals and for coin making.
- In the large scale cupellation, smelting is used to separate silver from lead and is applying heat to ore in order to extract metal.
So, the correct answer is “Option C”.

Note: - It is found that small scale cupellation is used in assaying. Cupellation ores are treated under high temperatures. The controlled operation to separate the metals like silver and gold, from base metals like zinc, copper, lead and others present in the ore or alloyed metal.