Question

Zone refining often yields 80-85% pure metal – True or False?

• A. True
• B. False

Answer 1

The correct option is B

False

Metals like silicon Gallium and Germanium which are already very pure are subjected to Zone Refining or Fractional crystallization. This process reduces the impurity to ppm level;it is based on the principle that the impurities tend to stay in the melt. On solidification, pure metal solidifies just ahead of the surface of the melt.

Refer to Zone refining for more details.