Zone refining is used for the purification of

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

Zone refining is a technique used primarily for which one of the following processes?

Impure aluminium is purified by

Silver obtained from argentiferous lead containing lead impurity is purified by

Blister copper is refined by stirring molten impure metal with green logs of wood because such wood liberates hydrocarbon gases (like $CH_4$). This process $X$ is called . . . . . . . . . and the metal contains impurities of $Y$ is . . . . . . . . .