Zone refining or Fractional crystallisation

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Zone refining or Fractional crystallisation:

Metals in high purity can be obtained in this method which is based on the difference in solubility in the liquid and solid states of the metal, and that of impurity, Ge,Si, and Ga used as semi-conductors are refined by this method. Gallium arsenide and indium antimonide used as semi-conductors are also refined by this method. In this method, a circular heater is fitted around a rod of impure metal and slowly moved over the rod. At the heated zone, the rod melts and as the heater moves, pure metals crystallises while the impurities drain away to the other part. The heater may have to be moved from one end to the other end of the rod more than once. 

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Siemens Ozoniser how Siemens Ozoniser work

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Rutile structure

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F - block element What are f - block elements

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