CONCLUSION:
Salicylic acid was converted into acetylsalicylic acid - Aspirin, which was obtained in 42.16 % yield. This is not an unusual that 100% yield was not obtained, because as the forward reaction - conversion of salicylic acid to aspirin- is occurring the reverse reaction- from aspirin to salicylic acid- is also occurring, converting some products to reactants. Perhaps sources of error in experiment also contributed in the % yield of experiment. The arrangement of the experiment, the measuring devices and the environment could have all contribution to the error. May be the boiling or the cooling time of the solution was not sufficient to dissolve or to crystallize the product. Or may be all of the solution containing the crystals was not filtered. There were several steps in the experiment in which the crystals had to be transferred from one container to another, so some of the crystals were perhaps lost during transferring. Melting point is a way to determine the relative purity of a substance.
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