Question

Zone refining is based on the principle that _________ .

Answer 1

Zone refining

• Zone refining is the metallurgical process of purifying metals.
• It is based on the principle that the impurities present in the metal dissolve more readily in the molten metal than in the solid state.
• It is done by melting the crystal in a narrow region.
• The molten crystal is allowed to flow over, the impurities will get molten and only the pure metals will be there.
• The pure metal is then recrystallized.
• Semiconductors and metals like Silicon $\mathrm{Si}$, Germanium $\mathrm{Ge}$ and Gallium $\mathrm{Ga}$ are purified by this method.

Hence, zone refining is based on the principle that the solubility of impurity in the molten state is more than in the solid-state.