What do you call a single unit of a chemical compound?

A single unit of a chemical compound is referred to as a monomer. Monomers are the smallest building blocks of more complex structures, capable of bonding with other similar or different molecules to form larger compounds known as polymers. In chemistry, understanding monomers is crucial because they serve as the fundamental components from which complex substances are constructed.

For instance, in the context of polymers, multiple monomers can join together in a chain-like structure to create long, repeating sequences that define the properties and functions of the polymer. This makes monomers essential in various fields, such as biochemistry, material science, and biology since they can influence the characteristics of the resulting polymers, including their strength, flexibility, and reactivity.

Other terms listed in the choices represent different concepts: polymers are made of many monomers, oligomers are short chains of monomers (not quite as complex as polymers), and biomolecules are large complexes crucial for biological functions that can contain multiple monomers or oligomers. Understanding the roles of these terms helps clarify the structure and function of compounds in chemical and biological contexts.