Tag: concentration of ore

Questions Related to concentration of ore

Which of the method used for the concentration of sulfide ores?

  1. froth floatation

  2. smelting

  3. magnetic separation

  4. gravity separation


Correct Option: A
Explanation:

This method is used for those metals whose ore gets preferably wetted by the oil and the gangue by the water. The sulphide ores preferably wetted by the oil and the gangue with the water.

In froth flotation process, pine oil is usually added to the gangue particles in the ore.

  1. True

  2. False


Correct Option: B
Explanation:

In froth flotation process, pine oil is usually added to the suspension of the powdered ore. Pine oil enhance non-wettability of the mineral particles.

Which of the following compound is used as froth stabliser?

  1. Fatty acid

  2. Aniline

  3. Xanthates

  4. Phosphoric acid


Correct Option: B
Explanation:

Here answer is option B

Aniline stabilize the froth before it is taken out for further treatment.
In this process, a suspension of a powdered ore is made with water. In this process, a suspension of a powdered ore is made with water. Collectors like pine oil, fatty acids and xanthates are added to it. Froth stabilizer like cresols, aniline stabilize the forth

The purpose of stream of air in leaching process of $Ag _2S$ is to?

  1. Oxidises $Na _2S$ formed into $Na _2S _2O _3$

  2. Oxidises $Na _2S$ formed into $Na _2S _2O _4$

  3. Oxidises $Na _2S$ formed into $Na _2O$

  4. Act as catalyst


Correct Option: A
Explanation:

In the leading of ${ Ag } _{ 2 }S$ (silver sulphide) with $NaCN$, a stream of air is passed because reversible nature of reaction between ${ Ag } _{ 2 }S$ and $NaCN$ and to oxidise ${ Na } _{ 2 }S$ formed into ${ Na } _{ 2 }{ SO } _{ 4 }$ and sulphur.

${ Na } _{ 2 }{ SO } _{ 4 }$ and sulphur $\Rightarrow { Na } _{ 2 }{ S } _{ 2 }{ O } _{ 4 }$

Froth flotation process is based upon :

  1. Magnetic property of gangue

  2. Specific gravity of ore particle

  3. Preferential wetting of ore particle by oil

  4. Preferential wetting of gangue particle by oil


Correct Option: C

Leaching is commercially carried out for in the concentration of:

  1. galena

  2. argentite

  3. copper pyrites

  4. tin stone


Correct Option: B
Explanation:

Leaching is a process in which the ore is dissolved in a suitable solvent, where the impurities remain undissolved. This method is used in the extraction of $Ag$ from Argentite where is, the ore is dissolved in sodium cyanide solution.

Which of the following method used for the concentration of copper pyrites?

  1. Magnetic seperation

  2. Gravity seperation

  3. Froth Floatation process

  4. None


Correct Option: C
Explanation:
This method is used when a higher ore contains impurities with higher density. This method is used for the concentration of Sulphide ores. (Eg: Copper pyrites, iron pyrites, Galena, Zinc blende etc.) Copper is mainly extracted from copper pyrites. After the concentration of its ore by froth flotation process, the ore is roasted in a current of air to remove arsenic, antimony and much of sulphur.

Which of the following process is used for concentration of ore?

  1. Froth flotation

  2. Electrolytic methods

  3. Smelting

  4. Hoop's process


Correct Option: A
Explanation:

Froth flotation method is used for the concentration of sulphide ores. 


The method is based on the preferential wetting properties with the frothing agent and water. In the given options, Galena (PbS) is the only sulphide ore.

Hence, option A is correct.

Which ore is concentrated by froth flotation method?

  1. Horn silver

  2. Bauxite

  3. Cinnabar

  4. Haemattie


Correct Option: C
Explanation:

Generally sulphide ores are concentrated by "Froth floatation" and cinnabar(HgS) is a sulphide ore.

Collectors are the substances which combine with sulphide ore and make them water repellant. Which of the following substance can act as collector?

  1. Sodium ethyl xanthate

  2. Sodium xenate

  3. Sodium pyrophosphate

  4. Adsorption


Correct Option: A
Explanation:

Sodium ethyl xanthate is used as collector in froth floatation process.