What peaks easily differentiate between carboxylic acids, aldehydes, ketones, and amides?
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Aldehydes have a characteristic peak around 2700-2800 $cm^{-1}$ due to the C-H stretch of the aldehyde group. Ketones do not have a characteristic peak in this region. Amides have a characteristic peak around 3300-3500 $cm^{-1}$ due to the N-H stretch. Show more…
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