Answer:
With the phenol of the salicylic acid.
Step-by-step explanation:
Hello,
In this case, we take into account that ferric chloride, FeCl₃, easyly reacts with phenol groups, in fact, that is one way to qualitatively substantiate the presence of phenols in an organic sample. Phenol groups are those hydroxiles (-OH) attached to an aromatic ring. Now, if FeCl₃ is added to a substance containing phenol functional groups, it will turn purple. For this case, since aspirin does not have any phenol group, in contrast to salicylic acid, which is used to produce aspirin, but actually has a phenol group, the aspirin sample will not react while the salicylic acid will turning purple, due to the aforesaid reason. Such purple color is shown off as a result of the formation of an iron-containing complex or chelant.
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