Define: 1. Atoms
2. Molecules
3. Particles.
Can a particle be a single atom?
Can a particle be a molecule?

Atom is a the smallest particle of a chemical element that can exist.

Molecules is a a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction.

Particles is a minute portion of matter.

A particle can be a single atom or a molecule ( a group of atoms held together by chemical bonds).

Atoms: a unit of the chemical element

Molecules: a group of atoms bonded together

Particles: tiny bits of matter

Yes, a particle can be a single atom.

Yes, because there's no restriction on how big or small in size particles are.

Explanation:

Atoms are in your body and even in the air you breath and molecules are with the atoms.

a:

by the combination of an unlimited number of elements