Same chapter2 marksDifficulty: Medium
Why is copper refined electrolytically rather than chemically?
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3 marksDifficulty: Medium
What is meant by the electrochemical series, and how does it decide which ion is discharged at the cathode?
Original Khojo Papers practice question — not from a past board paper.
Answer
The electrochemical series arranges ions in order of their tendency to be discharged at an electrode. At the cathode, the cation lower in the series, that is the one with the weaker tendency to stay as an ion, is discharged in preference to the others.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
So in the electrolysis of a dilute solution of a sodium salt, hydrogen is liberated in preference to sodium.
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