Identify 4 functional group: HO-HO-BENZENE RING-CH2-CH-NH2-C=O-OH

1)carboxylic acid functional group
2)amine functional group
3)alcohol functional group

i only know three is anyone can tell me the last functional group.please

Two Alcohols (OH groups), one carboxylic acid (CO2H), and one amine (NH2) equals four.

the benzene ring because it contains double bonds

1. Ester:COO

2. Ammonium salt NH4+ Cl-
3. Aromatic ring

The fourth functional group in the given molecule is an aldehyde functional group.

To identify functional groups, you need to understand the characteristic groups of atoms or groups of atoms that have specific chemical properties. Here's how you can approach identifying functional groups in a molecule:

1) Start by examining each part of the molecule individually. In the first molecule, HO-HO-BENZENE, you have a benzene ring (represented as BENZENE) connected with two hydroxyl groups (represented as HO-HO). The hydroxyl group (-OH) indicates an alcohol functional group.

2) For the second molecule, RING-CH2-CH-NH2-C=O-OH, break it down into smaller parts. You have a benzene ring (represented as RING), followed by a methylene group (represented as CH2), an amine group (-NH2), and a carboxyl group (-C=O-OH). The carboxylic acid functional group (-C=O-OH) and the amine functional group (-NH2) can be identified within this molecule.

So far, we have identified three functional groups: alcohol, carboxylic acid, and amine. Now, let's focus on the remaining part of this molecule.

3) After the amine group, we have a bond (represented as a dash) connected to a carbon atom followed by an oxygen atom (C=O). This arrangement indicates the presence of an aldehyde functional group.

Hence, the fourth functional group in the given molecule is an aldehyde functional group.