The purest zinc is made by

The formation of $Ni(CO)_4$ and its subsequent decomposition into $Ni$ and $CO$ forms the basis of the Mond process.
$Ni + 4CO$ $\xrightarrow{T_1} Ni(CO)_4$ $\xrightarrow{T_2} Ni + 4CO$
What are the values of $T_1$ and $T_2$?

Describe a method for refining nickel.

Outline the principles of refining of metals by the following methods:
$(i)$ Zone refining
$(ii)$ Electrolytic refining
$(iii)$ Vapour phase refining

Explain the distillation and liquation methods for the refining of metals.

In order to refine "blister copper",it is melted in a furnace and stirred with green logs of wood. The purpose is: