Consider the following statements :

Statement-I: In electrolytic refining, the impurities from the blister copper deposits anode mud which contains antimony, selenium, telluriun, silver, gold and platinum. (From copper pyrites)

Statement-2: In Serpeck's process, silica is removed by heating the bauxite to 1800° C with coke in a current of ${\mathrm{N}}_2$.

Statement-3: Chalcocite and azurite are ores of copper.

Statement-4: The tin is obtained by the carbon reduction of black tin

and arrange in the order of true/false

The following are the reasons for the correct answer,

1. The anode mud used in copper electrolytic refining contains antimony, selenium, tellurium, silver, gold, and platinum. These are contaminants found in copper blisters. They settle down behind the anode as anode mud because they are less reactive and unaffected by the copper sulphate and sulphuric acid solution. Tinstone, also known as cassiterite, is a non-magnetic material that also includes the magnetite (FeWO₄) impurity. Therefore, they are amenable to magnetic separation.

2. Bauxite ore that has silica  $\left({\mathrm{SiO}}_2\right)$ as the major contaminant can be purified using the Serpeck process

3. Chalcolite, cuprite, covellite, Azurite, and Malachite are the ores of copper.

4. The tin is obtained by the carbon reduction of black tin as ${\mathrm{SnO}}_2$ (black tin) is reduced by carbon as ${\mathrm{SnO}}_2+2\mathrm{CSn}+2\mathrm{CO}$

While smelting is done in a blast furnace during the extraction of lead, roasting is done in a reverberatory furnace

Hence, option D is correct.