Final answer:
The aldehyde among the given compounds is A) CH3CH2CH=O because it has the carbonyl group on an end carbon atom, making it an aldehyde according to the general aldehyde formula R-CHO.
Step-by-step explanation:
The compound that is an aldehyde among the options given is A) CH3CH2CH=O. Aldehydes typically have a carbonyl group (C=O) attached to at least one hydrogen atom. The general formula for an aldehyde is R-CHO, where R is a hydrocarbon group and -CHO signifies the aldehyde functional group with the carbon double-bonded to oxygen and bonded to a hydrogen. For example, ethanal (acetaldehyde), with the molecular formula CH3CHO, is an aldehyde where the R group is a methyl (-CH3) group.
Solution: a. This compound has the carbonyl group on an end carbon atom, which classifies it as an aldehyde as per the given definition. Option B) CH3CH2CH2CO2H is a carboxylic acid, C) CH3CO2CH3 is a ketone, D) CH3-O-CH3 is an ether, and E) CH2OH-CH2OH is a glycol or diol, which is an alcohol, so these are not aldehydes.