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Topic Redox reactions
Asked 4 times across 2 UPSC exams over 2 years (2024–2026), peaking in 2026.
Key insights
- Most tested in NDA — 3 of 4 PYQs
- Most asked in 2026
- Recurs across 3 years (2024–2026)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
NDA 2024 → GEO 2026
How the concept evolved
Rising — more than half its appearances (4 of 4) 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.
NDA2026
Consider the following pairs of reactions and properties: Reactions / Properties
- Fe(s) + 2HCl(aq) → FeCl₂(aq) + H₂(g) / Fe is reductant
- Zn(s) + CuSO₄(aq) → ZnSO₄(aq) + Cu(s) / Cu is being reduced
- Br₂(l) + 2I⁻(aq) → 2Br⁻(aq) + I₂(s) / Br₂ is reductant
- CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(l) / C atom in CH₄ is oxidized
Which of the above pairs are correct?
- A I and II only
- B II, III and IV
- C I, II and IV ✓
- D I, III and IV
✓ Correct answer: (C)
Science & Technology › Physics & Chemistry
GEO2026
Consider the following statements regarding oxidation
- There is loss of hydrogen
- There is gain of oxygen
- There is gain of electrons
- Oxidation state increases
Which of the statements given above are correct?
- A I, II and III
- B I, III and IV
- C I, II and IV
- D I, III and IV
Answer key not yet available (pending official release)
Science & Technology › Physics & Chemistry
NDA2025
Which one of the following statements regarding oxidation and reduction reactions is NOT correct?
- A If a substance loses hydrogen during reaction, it is reduced ✓
- B If a substance loses oxygen during reaction, it is reduced
- C If a substance gains hydrogen during reaction, it is reduced
- D If a substance gains oxygen during reaction, it is oxidized
✓ Correct answer: (A)
Science & Technology › Physics & Chemistry
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