Sample questions
You've seen the pattern — here are a few of the actual PYQs.
CDS2025
Variable oxidation numbers are possible for :
- A Sodium
- B Calcium
- C Iron
- D Lithium
Answer key not yet available (pending official release)
Science & Technology › Physics & Chemistry
CDS2016
Which one of the following statements is correct?
- A The oxidation number for hydrogen is always zero.
- B The oxidation number for hydrogen is always +1.
- C The oxidation number for hydrogen is always −1.
- D Hydrogen can have more than one oxidation number. ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
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