Explain the difference between (a) a synthetic and natural polymer. (b) a polyester and polyamide. (c) \(\alpha\) -and \(\beta\) -glucose.

Synthetic polymers are man-made, artificially produced polymers, typically derived from petroleum-based chemicals. They can be tailor-made with specific properties to suit a wide range of applications. Examples of synthetic polymers include plastics such as polyethylene, polypropylene, and polystyrene. Natural polymers are polymers that occur in nature, and they are usually biodegradable. Examples include proteins, nucleic acids, starch, and cellulose. These polymers are produced by living organisms and perform essential functions in their biology.

Both polyesters and polyamides are types of synthetic polymers. The main difference between them lies in their chemical structure, which affects their properties and applications. Polyesters are polymers that consist of ester functional groups in their main chain. They are usually made by polymerizing a diol (a molecule with two alcohol groups) and a dicarboxylic acid (a molecule with two carboxyl groups). Polyesters have good heat and chemical resistance and are often used in the production of fibers, fabrics, and consumer products like plastic bottles. An example of a polyester is polyethylene terephthalate (PET). Polyamides, on the other hand, have repeating amide functional groups in the main chain. Polyamides are formed by the polymerization of a diamine (a molecule with two amine groups) and a dicarboxylic acid. They are tough and have good abrasion resistance, which makes them suitable for use in textiles and engineering plastics. Nylon is the most well-known example of a polyamide.

α-glucose and β-glucose are isomers of glucose, meaning they have the same molecular formula (C6H12O6) but differ in their molecular structure. The difference between them exists due to the orientation of the hydroxyl (-OH) group on the first carbon atom (anomeric carbon). In α-glucose, the hydroxyl group on the anomeric carbon is positioned below the plane of the ring structure, which means that the hydrogen and hydroxyl groups on the first carbon atom are on the opposite sides of the molecule to the oxygen in the ring. In β-glucose, the hydroxyl group on the anomeric carbon is positioned above the plane of the ring, which means that the hydroxyl group on the anomeric carbon points in the same direction as the oxygen atom in the ring. This difference in structure affects the types of bonds that can form between glucose molecules, leading to different polysaccharides. α-glucose molecules can form α-1,4-glycosidic bonds, which result in the formation of starch (in plants) and glycogen (in animals). In contrast, β-glucose molecules can form β-1,4-glycosidic bonds, which result in the formation of cellulose, the main structural component of plant cell walls. These subtle differences in the structure of α- and β-glucose have significant implications for their biological roles and properties.