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Looking for a safe endothermic chemical reaction

  1. Feb 7, 2012 #1
    I’m not very well versed in chemistry so am asking for help. I’m looking for a couple of safe chemicals which combine to react (or dissolve etc.) endothermically. It doesn’t have to be an impressive reaction, it just has to be safe and not produce masses of gas (so that’s carbonate/ bicarbonate and acid out the window). I would preferably not like either substance to be water.

    If you know of any such chemicals (if they even exist), I would appreciate your help. Thanks :smile:
  2. jcsd
  3. Feb 8, 2012 #2


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    There are several dissolution reactions that are endothermic but that requires water of course. Of the safe ones that I know, all are performed in a water solution.
  4. Feb 8, 2012 #3
    Thanks for your reply. If I can't find an appropriate reaction (I'm not feeling optimistic) then I'll try dissolution.
  5. Feb 8, 2012 #4
    I'm not sure how you are going to manage it being safe and not have water as your solvent....

    Just throw some salt in ice water, show everyone how much faster you can freeze your beer, then give the professor one and I guarantee you will get an A.
  6. Feb 9, 2012 #5


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    I don't know why you want the solvent to not be water, anything else is likely to be more polluting.

    For aqueous solutions a fairly striking and practical one is urea. It has the advantage of being very water soluble - more than 1g/g and you get a quite noticeable cooling effect on making a concentrated solution. It is cheap. And afterwards you can spread it on your garden or pot plants as fertiliser. Not too concentrated near any plant and I believe an even 5-30 g/m2 is recommended.

    An outline of the interactions involved is here http://www.chemtopics.com/aplab/urea.pdf
  7. Feb 10, 2012 #6
    I was originally looking for a reaction but dissolution in water should work. Thanks.
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