How can you test for the presence of citral?
anything? somebody has to know something?
Are you looking for something that you could do yourself in say a basic science laboratory, or are you looking for current methods that are applied by scientists in the field?
I have found some papers on metabolism and disposition of citral in rats (paper 1, paper 2) and they use techniques like NMR-spectroscopy, gas chromatography, mass spectroscopy, and high performance liquid chromatography. These are all basically fancy ways of separating related compounds from one another and determining how much of each compound you have. If you can't get these references and/or want help with understanding these techniques, let us know.
I was looking for something a little less sophisticated. How could you identify citral? My guess is test its boiling point?
OK, testing for the "presence" of something can be quite different from testing whether a pure substance "is" something. So maybe you have a scenario like this. You have several vials of unknown substances and you want to know which one is citral. You're right in thinking about physical/chemical characteristics. Perhaps freezing/boiling point determination would be sufficient to differentiate the unkowns. As an aside, I'm pretty sure citral has a rather characteristic smell, it can be found in lemongrass, but I'm sure you were taught not to go around inhaling chemicals as a safe means of identifying them, so stick with the other tests.
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