The role of depressant in froth floatation process is :

The extraction of copper from pyrites is more difficult than from its oxide ores through reduction because -

1.  $∆{\mathrm{G}}_{\mathrm{f}}$ of HCl is less than that of ${\mathrm{H}}_2\mathrm{S} \mathrm{and} {\mathrm{CS}}_2$

2. $∆{\mathrm{G}}_{\mathrm{f}}$ of HNO₃ is less than that of ${\mathrm{H}}_2\mathrm{S} \mathrm{and} {\mathrm{CS}}_2$

3.  $∆{\mathrm{G}}_{\mathrm{f}}$ of ${\mathrm{Cu}}_2\mathrm{S}$ is less than that of ${\mathrm{H}}_2\mathrm{S} \mathrm{and} {\mathrm{CS}}_2$

4. $∆{\mathrm{G}}_{\mathrm{f}}$ of CuSO₄ is less than that of ${\mathrm{H}}_2\mathrm{S} \mathrm{and} {\mathrm{CS}}_2$

The common elements present in the anode mud in electrolytic refining of copper are -

1. Nitrogen, magnesium, sodium

2. Silver, gold, platinum, and antimony

3. Oxygen, sulphur, lithium

4. Nitrogen, magnesium, oxygen

The role of silica in the metallurgy of copper is :

The term “Chromatography” means -

1. Technique for the preparation of mixtures.

2. Technique for the separation of mixtures.

3. Technique for the separation of ore.

4. Technique for the preparation of aluminium.

Which of the following statements is true about the refining of nickel?

‘Cast iron’ is different from ‘Pig iron' because :

The correct statement among the following is:

Copper matte is put in silica lined converter to :

The role of cryolite in the metallurgy of aluminium is :