Which the following is an example of an organic compound that contains an attached hydroxyl group?
ester
alcohol
aldehyde
ketone

Alcohol is an example of an organic compound that contains an attached hydroxyl group.

Explanation:

Ester has the general formula of RCOOR'.Where R and R' can be same or different alkyl groups.

Alcohol has hydroxl group which act as functional group in alcohols attached to carbon chain.

They have general formula of ROH. Where R is an alkyl group.

Aldehydes has carbonyl group which act as functional group in aldehydes attached to carbon chain from only one side .

They have general formula of R-CHO. Where R is an alkyl group.

Ketones has carbonyl group which act as functional group in ketones, attached to carbon chains from both the sides .

They have general formula of R-(CO)-R'.Where R and R' can be same or different alkyl groups.

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explanation: