Aluminium metal is purified 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 $T_2$?

The zone refining of metal is based on the principle of

Which of the following elements is purified by vapour phase refining?

Which of the following metals is refined by vapour phase refining in the Mond process?

Aluminium is refined by