Question

Which one of the following is not a method of concentration of ores?

• A. Gravity separation
• B. Froth floatation process
• C. Electromagnetic separation
• D. Smelting

Answer 1

The correct option is D

Smelting

• The mineral which contains either metal or metal compounds in enough quantity that can be extracted easily and profitability is termed as ore.
• Impurities like sand and soil particles existing in any ore are termed as gangue. Elimination of these impurities from ore to extract the metal is termed as enrichment of ore or concentration of ore.
• Smelting is the process in which the concentrated ore is heated in the presence of a reducing agent like Carbon (C) to extract the desired metal. Hence, it is not a process for the enrichment of ore.
• Gravity separation is one of the methods to eliminate the unwanted substances from ore on the basis of their specific gravities.
• It is one of the processes utilized to concentrate the ore.
• The Froth floatation method is one of the methods to eliminate the impurities from sufide ores.
• The basic principle for this method is the distinct wetting properties of unwanted substance and ore.
• Electromagnetic separation is utilized to concentrate the ore if either gangue or ore are magnetic in nature.

Hence, option D is correct. Smelting is not a method used for concentration of ores.