Froth Flotation

Q.

Why is froath flotation method only used for sulphide ore? Give reason.

Q.

How do we separate two sulphide ores by Froth Floatation method?

Q.

Give the principles of:

(a) hydrolytic method, (b) froth floatation,

(c) electromagnetic separation.

Q. Extraction of copper from copper pyrite $CuFe{S}_2$ involves

1. Crushing followed by concentration of the ore by froth-floatation
2. Removal of Iron as slag
3. Self-reduction step to produce 'blister copper' following evolution of $S{O}_2$
4. Refining of 'blister copper' by carbon reduction

Q.

Froth floatation can be applied to non-sulphide ores.

1. True

2. False

Q.

Assertion – In froth flotation process sodium ethyl xanthate is used as collector.

Reason: Sulphide ores are water soluble.

1. Both assertion and reason are correct and the reason is the correct explanation for the assertion.

2. Both assertion and reason are correct but the reason is not the correct explanation for the assertion.

3. Assertion is correct but the reason is wrong

4. Assertion is incorrect but the reason is correct

Q. Give the equation for the reaction of NaCN with ZnS and PbS for froth flotation method of concentration

Q. Explain the floth floatation method with a neat labelled diagram.
[5 Marks]

Q.

In the froth flotation process, froth stabilizers and depressants must be added

1. True

2. False

Q.

Generally, for which of the following ores, froth floatation method is used for concentration?

1. Horn silver

2. Bauxite

3. Cinnabar

4. Haematite

Q.

Froth flotation can be applied to non-sulphide ores. True or False?

1. True

2. False

Q. Which of the following ores is best concentrated by froth floatation?

1. Malachite
2. Magnetite
3. Siderite
4. Galena

Q. Which of the following ores is best concentrated by froth floatation?

1. Galena
2. Siderite
3. Malachite
4. Magnetite

Q. Which of the following metal can not be extracted by smelting process?

1. Lead
2. Zinc
3. Iron
4. Aluminium

Q.

In froth floatation process, ______ is wetted by the oil and _____ is wetted by the water.

1. mineral, ore

2. mineral, gangue

3. ore, gangue

4. gangue, ore

Q.

Define froth floatation.

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

1. froth floatation
2. smelting
3. magnetic separation
4. gravity separation

Q. Heating the metallic ore in the presence of excess air is known as __________.

1. Roasting
2. Calcination
3. Smelting
4. Liquation

Q.

The principle behind froth floatation method involves the difference in the ________of the ore and the gangue particles.

1. solubility properties

2. wetting properties

3. weight

4. specific gravity

Q.

Froth floatation is usually applied for separation of _____ ores.

1. oxide
2. nitride
3. carbonate
4. sulphide

Q. Which of the following processes is related with the removal of sulphur by heating in the air?

1. Smelting
2. Calcination
3. Roasting
4. Annealing

Q. Which of the following statement(s) is (are) true ?

1. In process of the precipitation of silver sodium dicyano argentate (l), the zinc acts as reducing agent as well as a complexing agent.
2. In process of the roasting, the copper pyrites is converted into a mixture of $C{u}_{2}S$ and FeS which, in turn, are partially oxidised
3. Tin and lead both are extracted from their ores by self-reduction.
4. Limonite, haematite and magnesite are ores of iron.

Q. Write a note on froth floatation?

Q. Haematite, the ore of iron undergo roasting.
Which impurity is not removed by this method?

Q.

If both ore and gangue contain sulphur then ___ is used to separate ore from gangue in the froth flotation process.

1. Froth stabilizers

2. oils

3. depressants

4. Any of the above.

Q.

Generally, for which of the following ores, froth floatation method is used for concentration?

1. Horn silver

2. Bauxite

3. Cinnabar

4. Haematite

Q.

Assertion – In froth flotation process sodium ethyl xanthate is used as collector.

Reason: Sulphide ores are water soluble.

1. Both assertion and reason are correct but the reason is not the correct explanation for the assertion.

2. Assertion is correct but the reason is wrong

3. Assertion is incorrect but the reason is correct

4. Both assertion and reason are correct and the reason is the correct explanation for the assertion.

Q. Which of the following methods are used for concentration of ores?

1. Gravity seperation
2. Froth floatation
3. Roasting
4. Calcination

Q.

Of the following reduction processes :

I. $F{e}_2{O}_3+C\to Fe$

II. $ZnO+C\to Zn$

III. $C{a}_3(P{O}_4{)}_2+C\to P$

IV. $PbO+C\to Pb$

Correct processes are :

1. II and IV
2. all of these
3. III and IV
4. I , II and IV