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NEET levelSingle correct optionDifficulty 1 of 3mt115

Cryolite, , is added to alumina in the Hall-Heroult cell mainly to

  1. Aact as the reducing agent for alumina
  2. Blower the melting point of the mixture and increase its electrical conductivity
  3. Coxidise the impurities present in alumina
  4. Dserve as the cathode material

Answer: B

Pure alumina melts near and conducts poorly. Dissolving it in molten cryolite (with some fluorspar) gives a conducting melt that can be electrolysed at a much lower temperature. Cryolite is not consumed as a reducing agent.
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