Indian Forest Service (Mains), Chemistry optional · 2025 · Paper II
Q5(f). Structure from combined spectra
Question
Derive the structure of C₁₀H₁₂O₂ from the listed IR, NMR and MS data, assigning each signal. [IR, ¹H NMR and mass spectral data given in the paper]
Answer in brief
The structure is 4-ethoxyacetophenone, p-EtOC₆H₄COCH₃.
Part of VKC Basic
Read the key points and the full model answer with VKC Basic
VKC Basic (₹999 for 6 months) opens every solved answer, the notes, the handbook and the daily answer archive. Every Mains test series includes it.
The full model answer
As written for the answer booklet: the diagram carries the working, the lines stay short. Read here only; it is not offered as a download.
The handwritten model answer pages open with the VKC plan.
Coversstructure elucidation4-ethoxyacetophenonecombined spectral problempara-disubstituted benzene NMRdegree of unsaturation
All parts of Question 5
- 5(a) Edman degradation5 marks
- 5(b) Complementary base pairs in RNA5 marks
- 5(c) Photoreduction of benzophenone5 marks
- 5(d) Proton NMR of dry ethanol5 marks
- 5(e) Mass fragmentation of acetic anhydride5 marks
- 5(f) Structure from combined spectra15 marks