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प्रश्न
Answer the following questions based on the extraction of aluminium from alumina by Hall - Heroult’s Process :
What is the function of cryolite used along with alumina as the electrolyte?
उत्तर
In the extraction of aluminium, the metal is to be isolated from alumina (Al2O3) by carrying out its electrolytic reduction. The melting point of alumina veery high (2323K).
- It is therefore, mixed will cryolite ( Na2AlF6 ) which lowers its melting point to 1173 k.
- More over, cryolite also increase the electrical conductivity of alumina.
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