Question

(i) What is the principle behind Zone refining' of metal ? Name an element which is refined by this method. 

(ii) Write the name of the metal refined by each of the following processes: 

(a) Distillation 

(b) Liquation

Answer 1

(i) Impurities are more Soluble in the molten state than in the solid state of the metal.

Example: Ge/Si/B (any other)

(ii) (a) Zn/Hg

(b) Sn

Detailed Answer: 

(i) Zone refining is based on the principle that the impurities are more soluble in the melt than in the solid state of the metal. Silicon, boron etc. are refined by this method.