UPSC Combined Geo-Scientist, Mains · 2023 · Mains Paper III
Q9(a). Woodward–Fieser rules: a dienone, a tetraene and a cyclopentenone
Question
Using Woodward's rules, calculate the λmax value for the following compounds: I, II and III. [Structures I to III given in the paper]
Model answer
The free solution for 2023 answers questions 1, 4, 5, 6, 7 and 10, the ones picked in its time plan. Question 9 is answered in full in the Geo-Scientist Chemistry Paper III, 2021 to 2025 book, with every part of every paper.
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UPSC Combined Geo-Scientist (Main) Chemistry Paper III: Model Answers 2021 to 2025
- All ten questions of each paper, with the question printed above its answer
- Instruments drawn as labelled diagrams, numericals worked with units
- Topic-wise weightage and a topic-wise index
CoversWoodward–Fieser rulesλmax calculationconjugated dienesenonesUV spectroscopy
All parts of Question 9
- 9(a) Woodward–Fieser rules: a dienone, a tetraene and a cyclopentenone10 marks
- 9(b) Trialkylborane to aldehyde, ketone, alcohol and tertiary alcohol10 marks
- 9(c) C=O stretching order: benzophenone, cyclohexanone, indan-2-one5 marks
- 9(d) Products of five reactions5 marks