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UPSC Combined Geo-Scientist

Chemist

  • 2 objective papers
  • 120 questions each
  • 2 h per paper
  • 100 + 300 marks

Prelims Paper II covers chemistry.

UPSC Combined Geo-Scientist, Prelims · 2025 · Paper II, Chemistry · Q100 of 120

Geo-Scientist Prelims 2025 Chemistry Q100: The correct description of the mechanism adopted by the following…

QuestionReaction mechanism / Mannich base elimination-addition

The correct description of the mechanism adopted by the following transformation is :

UPSC Combined Geo-Scientist Prelims 2025 Paper II (Chemistry), Q100: figure printed with the question
  1. (a) E1 elimination followed by 1,4-conjugate addition of cyanide anion
  2. (b) E2 elimination followed by 1,4-conjugate addition of cyanide anion
  3. (c) E1cB elimination followed by 1,4-conjugate addition of cyanide anion
  4. (d) Straightforward SN2 pathway involving cyanide anion as nucleophile

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