WBJEE · Chemistry · s Block Elements
In the extraction of Ca by electro reduction of molten \(\mathrm{CaCl}_{2}\) some \(\mathrm{CaF}_{2}\) is added to the electrolyte for the following reason:
- A To keep the electrolyte in liquid state at temperature lower than the m. p. of \(\mathrm{CaCl}_{2}\)
- B To effect precipitation of Ca
- C To effect the electrolysis at lower voltage
- D To increase the current efficiency
Answer & Solution
Correct Answer
(A) To keep the electrolyte in liquid state at temperature lower than the m. p. of \(\mathrm{CaCl}_{2}\)
Step-by-step Solution
Detailed explanation
Hint: \(\mathrm{CaF}_{2}\) decreases the melting point of \(\mathrm{CaCl}_{2}\)
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