# Tag Info

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Please don't apply the reversible CV diagram on something which is clearly a non-classical cyclic voltammogram. When you experimentally don't get the shape as predicted by the theory, it means it that particular theoretical model does not apply in your case. Look at three different types of voltammograms in this picture. Does your CV look like a reversible ...

2

I offer the following explanation for the fragments of the mass spectrum of methyl salicylate (1, m/z 152). Loss of methoxy radical affords acylium ion 2 (m/z 121). Subsequent loss of a proton from 2 gives rise to the base peak 6-oxomethylidenecyclohexa-2,4-dien-1-one (3). Loss of carbon monoxide from 3 produces carbene 4, which rearranges to cyclopenta-2,4-...

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No, sample volume will not effect quantitation if the following conditions are met: 1) you are comparing samples in tubes with the same inside diameter, 2) you have enough sample volume so that the sample liquid extends at least a few diameters past the ends of the RF coil, 3) your shim is good enough so that the peaks you want to measure do not ...

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Third edition (latest offline edition) of the ACS Style Guide (currently known as The ACS Guide to Scholarly Communication) has a section devoted to reporting analytical data, including mass-spectrometry and EIMS in particular [1, p. 275]: Mass Spectrometry MS $m/z$ (relative intensity): $238.2058~(44.8\%),$ $195.1487~(100\%),$ $153.1034 ~(21.2\%).$ GC–MS \$...

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Wow. This is a very bad question (the exam/assignment, not the OP's). There is no way that you can categorically determine the structure of this based only on the information given. This would have to be open-book providing access to chemical shift tables in the very least. Peaks are poorly labelled and what's more, I believe the molecular mass is incorrect. ...

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Interesting Problem and quite a nailbiter. I will try to sort some of my ideas, even thought this won't be a full answer. This looks like a question from an exam. Did you have any reactions during study with hydrochloric acid and propanoyl chloride (acid chloride of propionic acid). So maybe look into different reactions of acid chlorides. As @...

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The short answer: Do not rely on the SIM trace alone. Amplify the representation of the trace about the TIC (total ion current) until you see a reasonable peak intensity at the same retention time as in your SIM traces (perhaps a time spectrum, but not a mass spectrum). Then integrate with the peak-shaped cursor (currently shown in the magenta coloured ...

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Neat or pure for organic chemists has a different meaning for analytical chemists. What does your manufacturer label say? 100% pure methyl salicylate? That is not possible. It must have closely related impurities. Did you try a thin layer chromatography experiment with this sample? There is no concept of 100% pure substance in analytical chemistry, ...

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There are various colors of chemical compounds because color is dependent on all of the interactions of all the components of the mixture, including the concentration. Some materials can appear to be one color in dilute solution, but a significantly different color in concentrated solution, because the level of absorption at a particular wavelength becomes ...

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I feel that you misunderstood what the authors were trying to say in that textbook. Forget about everything for the time being. Imagine if you injected a single analyte band into an HPLC column of length L at a constant flow rate. You waited for some time, and now the band is exiting the column. For simplicity, assume that the band is rectangular. Ask ...

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