Topic Oxidation
Asked 10 times across 4 UPSC exams over 46 years (1980–2026), peaking in 2023.
Key insights
- Most tested in CDS — 4 of 10 PYQs
- Most asked in 2023
- Recurs across 7 years (1980–2026)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CSE 1980 → CDS 2014 → NDA 2023 → GEO 2026
How the concept evolved
Rising — more than half its appearances (8 of 10) 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
Which of the following are oxidation reactions?
- Rusting of iron
- Burning of fuel
- Rancidity of oils and fats
- Browning of fruits
Select the correct answer using the code given below.
- A I, II and III only
- B I, II and IV only
- C III and IV only
- D I, II, III and IV ✓
✓ Correct answer: (D)
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
What happens when the fat and oil containing food materials are left outside for a long time?
- A Fats and oils in the food get oxidized ✓
- B Fats and oils in the food get reduced
- C Fats and oils in the food get ice-covered
- D No reaction takes place
✓ Correct answer: (A)
Science & Technology › Biology & Health
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