Which functional group is associated with alcohols?

The functional group associated with alcohols is indeed the hydroxyl group. The hydroxyl group consists of an oxygen atom bonded to a hydrogen atom (-OH). This structure is characteristic of alcohols, which are organic compounds where one or more hydroxyl groups are attached to a carbon atom.

The presence of the hydroxyl group not only defines the chemical nature of alcohols but also contributes to their physical properties, such as increased polarity and ability to form hydrogen bonds. This polar nature allows alcohols to interact with water and increases their solubility in aqueous solutions compared to hydrocarbons. Therefore, the hydroxyl group is essential for determining how alcohols behave in biological systems and in chemical reactions.

Other functional groups listed, like carboxyl, amino, and phosphate, serve different roles in organic chemistry and biochemistry. The carboxyl group (-COOH) is found in acids, amino groups (-NH2) are present in amino acids, and phosphate groups (-PO4) are critical in energy transfer and nucleic acids, but none of these are characteristic of alcohols.