If a metal has low oxygen affinity,then the purification of the metal may be carried out by:

The zone refining method is used for which of the following?

Explain vapour phase refining.

Which method of refining nickel is represented by the following equation?
$Ni$ (impure) $+ 4CO$ $\xrightarrow{320 \ K} Ni(CO)_4$ $\xrightarrow{420 \ K} Ni$ (pure) $+ 4CO$

In the electrolytic refining of an impure metal,a rod of impure metal is used as the anode and a rod of pure metal is used as the cathode,and the aqueous solution of its salt is electrolyzed. Which of the following metals cannot be refined by this method?

The method,which is based on the principle that "different components of a mixture are differently adsorbed on an adsorbent" is called