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Topic Electrolysis
Asked 3 times across 3 UPSC exams over 4 years (2021–2025), peaking in 2021.
Key insights
- Most tested in CDS — 1 of 3 PYQs
- Most asked in 2021
- Recurs across 2 years (2021–2025)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
NDA 2021 → CISF 2021 → CDS 2025
How the concept evolved
Rising — more than half its appearances (3 of 3) are since 2016.
Related concepts
Ideas UPSC tests alongside this one — keep exploring.
Sample questions
You've seen the pattern — here are a few of the actual PYQs.
CDS2025
Which one of the following metals is widely extracted by the electrolysis of its molten compound ?
- A Cu
- B Au
- C Sn
- D Na
Answer key not yet available (pending official release)
Science & Technology › Physics & Chemistry
NDA2021
In electrolytic refining of copper, the electrolyte is a solution of
- A acidified copper chloride.
- B acidified copper sulphate. ✓
- C potassium chloride.
- D sodium sulphate.
✓ Correct answer: (B)
Science & Technology › Physics & Chemistry
CISF2021
When electricity is passed through brine, it produces
- A NaCl
- B NaOH ✓
- C KCl
- D KOH
✓ Correct answer: (B)
Science & Technology › Physics & Chemistry
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