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Multiple choice chemistry principles of metallurgy concentration of ore concentration of ores general principles of metallurgy

 Name the metal which are associated with the following term in their extraction from their ores. Magnetic separation:

  1. tin stone and chromite ore

  2. copper stone and chromite ore

  3. tin stone and iron ore

  4. none of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
 This method is adopted when either ore or the impurities are magnetic in nature. They are separated from each other by means of magnetic separators. Eg: $SnO _2$ (Non magnetic) in $Fe _3O _4$ (magnetic)
Multiple choice chemistry principles of metallurgy concentration of ore concentration of ores general principles of metallurgy

Sulphide ore of copper can be concentrated by froth floatation process.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Froth Floatation Process:- The process is best suitable for sulphide ores. The process is based on different wetting characteristics of the ore and gangue particles with water and pine oil. The ore is wetted by oil and impurities are wetted by water. Ore particles are adsorbed on potassium or sodium ethyl xanthate (as collector) and come at the surface along with the froth. Froth stabilisers (cresols, aniline) stabilise the froth. So sulphide of copper can be concentrated by froth floatation process.
Multiple choice chemistry principles of metallurgy concentration of ore concentration of ores general principles of metallurgy

Sulfide ores are usually dressed by the _____ process.

  1. sieve process

  2. froth floatation

  3. magnetic floatation

  4. none of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Froth floatation process is based on the principle that the metallic sulphide particles of ore are preferentially wetted by oil and the gangue particles by water.
Sulphide ores being lighter are easily wetted by oil to come on the surface of solution with froths during froth floatation process, leaving behind heavy matter of gangue wetted by water.
Sulphide ores are usually dressed by froth floatation process.

Multiple choice chemistry principles of metallurgy concentration of ore concentration of ores general principles of metallurgy

The oil used in the froth floatation method for the purification of ore is _________.

  1. Coconut oil

  2. Olive oil

  3. Pine oil

  4. Castor oil
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Froth Floatation process is suitable for sulphide ores. The process is based on different wetting characteristics of the ore and gangue particles with water and pine oil. 

The ore is wetted by oil and impurities are wetted by water. Ore particles are adsorbed on potassium or sodium ethyl xanthate (as a collector) and come at the surface along with the froth. Froth stabiliser (cresols, aniline) stabilise the froth. 

So, the correct option is $C$
Multiple choice chemistry principles of metallurgy concentration of ore concentration of ores general principles of metallurgy

During concentration of _____ ores by froth floatation process potassium ethyl xanthate is added.

  1. sulphide

  2. carbonate

  3. halide

  4. amide
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During concentration of sulphide ores by froth floatation process potassium ethyl xanthate is added.
Ethyl xanthate, potassium ethyl xanthate and similar compounds compounds behaves as collector and attaches themselves by polar groups to ore particles making that hydrophobic and i.e., why ore particles are passed into froth.

Multiple choice chemistry principles of metallurgy concentration of ore concentration of ores general principles of metallurgy

Ores like magnetite or tungstates in tin ores are concentrated by ______.

  1. Froth floatation

  2. Magnetic separation

  3. Gravity separation

  4. Electrostatic separation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Magnetic Separation:- This method is adopted when either ore or the impurities are magnetic in nature. They are separated from each other by means of magnetic separators.
Eg: $SnO _2$ (Non magnetic) in $Fe _3O _4$ (magnetic)
Multiple choice chemistry principles of metallurgy concentration of ore concentration of ores general principles of metallurgy

The substance added in water in the froth floatation process is

  1. Olive oil

  2. Pine oil

  3. Coconut oil

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Froth floatation process: This process is best suitable for sulphide ores. It is based on different wetting characteristics of the ore and gangue particles with water and pine oil. The ore is wetted by oil and impurities are wetted by water. Ore particles are adsorbed on potassium or sodium ethyl xanthate (as collector) and come at the surface along with the froth. Froth stabiliser (cresols, aniline) stabilises the froth.

Multiple choice chemistry principles of metallurgy concentration of ore concentration of ores general principles of metallurgy

Ore dressing for iron is done by:

  1. froth floatation process

  2. magnetic separation

  3. hand picking

  4. all of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In the field of extractive metallurgy, mineral processing, also known as ore dressing, is the process of separating commercially valuable minerals from their ores. 

Ore dressing for iron is done by magnetic separation.
So answer is B.