In Problem 2 tell how many principal signals would probably be observed in the p
ID: 574920 • Letter: I
Question
In Problem 2 tell how many principal signals would probably be observed in the proton NMR spectrum of each compund, and predict the relative areas under the sig- nals An NMR spectrum shows two principal signals with an area ratio of 3:1. Based on this information only, which of the following structures are possibilities? (b) CH2-CHCO2CH (a) CH2 CHCH (c) CH CH CH2CH2CH2CH3 (d) CH CH CH3 (e) CH2-C(CH3)2 (f) CH3CO2CH Calculate the ratios of the different types of hydrogen atoms in a sample when the steps of the integration curve measure 81.5, 28, 55, and 80 mm. A 'H NMR spectrum shows four signals with integration curve heights of 4.0,3.5,5.4, and 5.5 cm. What is the ratio of the types of protons in this sample?Explanation / Answer
4. Answer is (e) CH2=C(CH3)2 and (d) CH3CH2CH3
In CH2=C(CH3)2, the underline protons are chemically identical, giving rise to peak corresponding to 6 protons, the rest of two protons are identical, so the they give rise to 2 proton signal, so the ratio is 6:2, which equals to 3:1.
Similarly in CH3CH2CH3, the underline protons are chemically identical, giving rise to peak corresponding to 6 protons, the rest of two protons are identical, so the they give rise to 2 proton signal, so the ratio is 6:2, which equals to 3:1.
5. Here the lowest number is 28, and 55 is almost double of 28 and 80 and 81.5 are almost thrice of 28, so the ratio of different types of protons will be 3:1:2:3.
6. Divide all the values with 3.5 and we get 1.14, 1, 1.54, 1.57. We need whole numbers. If we multiply all numbers with 2, we get values approximately 2, 2, 3 and 3. So the ratios will be 2:2:3:3.
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.