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General Principles and Processes of Isolation of Elements — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryGeneral Principles and Processes of Isolation of Elements3 Marks
Question
  1. Write the principle of electrolytic refining.
  2. Why does copper obtained in the extraction from copper pyrites have a blistered appearance?
  3. What is the role of depressants in the froth floatation process ?
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Answer

  1. On passing current through the electrolytic cell , the pure metal gets deposited on the cathode.
  2. Evolution of $SO_2$ gas
  3. It selectively prevents one of the sulphide ores from coming to the froth.

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