Nylon is a polyamide, which is a form of condensation polymer. Polyamides are made by reacting a dicarboxylic acid monomer with another monomer termed a diamine. Water is released as a byproduct of the process as the two monomers create an alternating chain. The resulting polymer is a linear molecule with many functional groups available for further reaction or modification. Within the context of polymers, to be considered polyamides, molecules must contain both amino and carboxylic acid groups. Nylon fibers are often treated with agents that modify their surface properties or help them dissolve in water. For example, nylon fibers can be oxidized using sodium hypochlorite solution to make them more hydrophilic (water-loving) and thus more soluble in water. Oxidizing agents such as chlorine bleach break down the nylon polymer chain, exposing new reactive sites. These sites can then react with chemicals called amines, which are found in many proteins and peptides. This reaction produces chloroacetic acid and ammonia, which cause the dissolved fibers to become cloudy with each addition. This process is used to color nylon fabrics various colors, including white. Amphoteric materials like nylon can be classified as either acidic or basic depending on how they respond to acids or bases, respectively. Nylon is considered an amphoteric material because it has both amino and carboxyl groups.