Question

The method of zone refining of metals is based on the principle of:

• A. greater noble character of the solid metal than that of the impurity
• B. greater solubility of the impurity in the molten state than in the solid
• C. greater mobility of the pure metal than that of impurity
• D. higher melting point of the impurity than that of the pure metal

Answer 1

Answer: (B)

greater solubility of the impurity in the molten state than in the solid

The zone refining method is based on the difference in the solubility of the impurities in the molten and in the solid state of the metal.
In zone-refining method the molten zone contains more impurity than the original metal.