MCQ
Zone refining is a method to obtain:
- AVery high temperature.
- BUltra pure $Al.$
- ✓Ultra pure metals.
- DUltra pure oxides.
✓
Answer
Correct option: C.
Ultra pure metals.
Zone refining is based upon fractional crystallization as the impurity prefers to stay in the melt and on solidification only pure metals solidifies on the surface of melt.
In this process solubility of the impurities in the metal in molten and solid states is different.
This process is known as ultra$-$purification because it results in impurity level decreasing to $\text{ppm}$ level.
In this process solubility of the impurities in the metal in molten and solid states is different.
This process is known as ultra$-$purification because it results in impurity level decreasing to $\text{ppm}$ level.
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