Final answer:
Aldehydes and ketones peak on IR in the range of 1700-1750 cm-1 due to the carbonyl double bond. This absorption peak is a dead giveaway for the presence of a carbonyl group.
Step-by-step explanation:
Aldehydes and ketones peak on IR in the range of 1700-1750 cm-1. The key absorption peak is from the carbonyl double bond. This peak is a dead giveaway for the presence of a carbonyl group.
Aldehydes and ketones tend to absorb in the shorter wavelength end of this range (1700-1750 cm-1).