What are examples of compounds and non-compounds?

Jun 15, 2017

A compound is a multi-atom substance where two or more different elements are in each formula unit (for ionic compounds) or molecule (for covalent compounds).

The following are examples of compounds.

• $\text{HF}$, hydrofluoric acid, is a molecule, but can also be called a binary compound; more specifically, a binary acid. It contains two different elements.
• ${\text{CO}}_{2}$, carbon dioxide, is generally considered a molecule, but can also be called a compound. It contains two different elements.
• $\text{CH"_3"COOH}$, acetic acid, is a molecule, and is also a compound. It contains three different elements.

The following are examples of NOT compounds.

• ${\text{Br}}_{2}$, bromine, is a diatomic element, or a molecular element. Only one element is in its structure though, so it is not a compound.
• $\text{Ar}$, argon, is an atom; thus, it cannot be multi-atomic, and consequently is not a compound.
• ${\text{S}}_{8}$, sulfur, is an octatomic element, or a molecular element. Only one element is in its structure though, so it is not a compound.