Practical investigations
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Hello.
Just a quick question: Why do we not hydrolyse the aspirin in the colorimetry? How does the solution turn purple with the addition of Fe(III) chloride then if it is aspirin and not salicylic acid?
Thank you!!
Corrie writes .......
The coloured complex with Fe3+ ions is only formed by salicylic acid, not aspirin - see our tutorial on Aspirin Investigations (via the 'Practical Investigations' link on the Re:act Homepage).
So if you don't hydrolyse the aspirin first, then all colorimetry will tell you is how much salicylic acid impurity is present in your aspirin sample.
Risk assessment
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updated: 07 January 2008
