What is the term for the abbreviated expression that represents a chemical compound?

The correct answer is the term "Formula," which refers to the abbreviated expression that indicates the composition of a chemical compound. In chemistry, a formula uses symbols to represent the elements in the compound and numerical subscripts to show the quantity of each element present. For example, H₂O represents water, where 'H' stands for hydrogen and 'O' stands for oxygen, with the subscript '2' indicating that there are two hydrogen atoms for every one oxygen atom.

In contrast, a compound refers to a substance formed when two or more chemical elements bond together, but it does not specifically denote the abbreviated expression. Molecular weight is a term that describes the mass of a molecule based on the sum of the atomic weights of its constituent elements, rather than the representation of the compound itself. An equation, in this context, typically reflects a chemical reaction, illustrating reactants and products rather than serving as an abbreviation for a compound. Overall, understanding that a formula succinctly encapsulates the makeup of a chemical compound is key in chemistry and related fields.