There was much material not present on exam 1 that I expected to be. One question i found to be absent from the exam was the chemical shift calculation (parts per million). Discussed on pages 495-496 of chapter 14, the chemical shift is calculated by dividing the observed chemical shift (Hz) down field from the TMS, by the frequency of the NMR spectrometer. Also absent from the exam was the calculation for frequency and the ratios between different NMR chemical shifts. To find the frequency of the NMR spectrometer, you simply multiply the observed chemical shift (Hz) and the chemical shift (ppm) and you will get the frequency of the NMR spectrometer in MHz.
Also absent from the exam was the problems involving drawing charged mass spectrum fragments given the m/z values. This is done by calculating the appropriate number of carbon and hydrogen atoms compared to the given m/z value and arranging them likewise.
I agree. I thought there would be questions like this also. Calculating chemical shift isn't a difficult thing to do if you know the formula so I thought there would be a question like that just to give us some "easy" points (if you studied that). I also practiced how to draw the fragments of a mass spectrum and was surprised to see that they didn't appear on the test. Especially since there was a problem over that on the Chapter 13 quiz and a few Sapling problems. Overall, I thought that there were questions that should have been on the test because we spent a lot of time going over them in class and they appeared on quizzes but weren't. Ones just like these and the one I wrote about in my blog. It was a good learning experience and hopefully the class will do better on the next one.
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