The process of concentrating an ore by taking advantage of the difference in density between the ore and the gangue is: MCQ with Answer and Explanation

The process of concentrating an ore by taking advantage of the difference in density between the ore and the gangue is:
A. Froth flotation
B. Magnetic separation
C. Hydraulic washing
D. Leaching
Answer: Option C
Solution (By JKExamLibrary)
Hydraulic washing, also known as gravity separation, is based on the difference in specific gravities (densities) of the metallic ore and the associated impurities (gangue). The powdered ore is washed with a running stream of water; the lighter impurities are carried away, leaving the heavier ore particles behind.

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Urea contains what percentage of nitrogen approximately?
A. 46%
B. 15%
C. 35%
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Correct Answer: Option A


Explanation:
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Correct Answer: Option B


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The metal used in the manufacture of stainless steel is:
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Correct Answer: Option D


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