When is a molecule considered a compound?

A molecule is considered a compound when it contains atoms of more than one element. This definition reflects the fundamental nature of compounds in chemistry. Compounds are distinct substances formed from two or more different elements that are chemically bonded together. An example of a compound is water (H2O), which consists of hydrogen and oxygen atoms bonded together.

While other options discuss important concepts related to molecules, they do not define what makes a molecule specifically a compound. For instance, a molecule containing only one type of atom refers to an element, not a compound. The formation of ionic bonds is just one type of chemical bond that can occur in compounds but does not apply to all compounds, as some are held together by covalent bonds. Lastly, the charge of a molecule relates to its ionic or molecular character but is not a defining feature of compounds since many neutral compounds still comprise more than one type of element.