Separating organic compounds by fractional crystallisation
Sometimes aspirin (acetylsalicylic acid)is present in analgesic tablets such as a calcium salt, which is water soluble. How would you separate the acetylsalicylic acid in this case?
Some over the counter medicines contain organic amines. How would you modify the extraction scheme to separate and purify such an amine( assume it is insoluble in water)
Some liquid analgesic preparations contain sugar. Where will the sugar be at the end of a separation scheme .
well you are looking for some property to exploit when you are doing a separation....
in this case you can change the solubility of the components....
the tablet is soluble in water , so when you dissolve it you will get a solution of Ca ions and the acetylsalicylic acid
normally you would add base to an acid to make it more soluble in water, the ionic form of the base is more soluble
then you can precipiate the Ca by adding an ion that causes a precipitate....
extract the water (which will contain the deprotonated acid) and they are separated