Which statement defines a "Particle" correctly?

A particle is often defined as a small localized object that can be described by physical properties such as volume and mass. In the context of science, particularly physics and chemistry, a particle can refer to various entities, including atoms, molecules, ions, and subatomic particles (like electrons and protons). The choice that states a particle is "not considered a molecule" acknowledges that while some particles are indeed molecules (which are made up of two or more atoms bonded together), not all particles fit this definition.

For example, individual atoms and subatomic particles are considered particles but are not molecules. Therefore, this statement correctly provides a broader understanding of what a particle is by distinguishing it from solely being a molecule. The other options either define a particle too narrowly, limiting its definition to molecules or specific types of atoms, or they confuse the conceptual understanding with a measurement rather than recognizing the particle as a discrete entity in itself.