|MadSci Network: Biochemistry|
The aging of aspirin (acetyl salicylic acid) is a low hydrolysis process and the acetic acid can be noted by its vinegar smell. The hydrolysis ratios are well known by the pharmaceutical industries, and the length of its shelf-life is due to this kinetic process. The process develops more quickly in the presence of moist air or flasks that are badly closed, in which case the aspirin must be disposed of.
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