Each of the 20 amino acids has a specific side chain, known as an R group, that is also attached to the α carbon. The R groups have a variety of shapes, sizes, charges, and reactivities.
Additionally, each protein contains a wide range of functional groups (groups of atoms attached to the amino acids that participate in specific chemical reactions) that may affect its final shape.
Understanding the properties of different compounds caused by functional groups and intermolecular forces is important. A common carboxylic acid is ethanoic acid, vinegar. Carboxylic acids are ...