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Question
Explain in brief types of extraction of highly reactive metals according to their reactivity.
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Solution
Extraction of highly reactive metals:
- Highly reactive metals such as sodium, magnesium and calcium are obtained by electrolytic reduction.
- The metals are deposited at the cathode (negatively charged electrode), whereas chlorine gas is liberated at the anode (positively charged electrode).
E.g. For extraction of sodium metal, cathode and anode reactions are as follows:
At cathode: \[\ce{Na+ + e^- -> Na}\] (Reduction)
At anode: \[\ce{2Cl- -> Cl2 + 2e^-}\] (Oxidation)
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