Question

Technique N Naclear Magnetic Resonance Specicpy 153 Problem 5-C смо 82.2 (3H) 85.9-6.3 (3H) TMS 3 55 50 4 405 30 25 20 15 10 CDCl TMS SOURCE Reprinted with permission of Aldrich Chemical The H NMR spectrum of cyclohexane shows one singlet. If the sample is cooled so C, the spectrum changes. Predict the spectrum of the cooled cyclohexane and explain why the spectrum changes as the solution is cooled. 6. What is the purpose of TMS? 7. Predict the chemical shift of the protons in methylithium (CHiLi). in an organic compound has a chemical shift of 83.4 in a 60 MHz he prom, What will be the chemical shift if the spectrum is recorded using a 90 MHz NMR instrument? oping between two protons in an alkene is 10.8 Hz at 60 MHz. What will be e valae of the coupling constant between these same two protions at 200 MHz 9. The 2.2

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