Répondre :
An atom consists of a nucleus of protons and neutrons, and a cloud of electrons. It is characterised by an atomic number that corresponds to its number of protons, which is also that of its electrons.
An atom is a small particle made up of a Nucleus around which electrons move. Atoms associate into molecules or change into ions. The nucleus is itself composed of nucleons: neutrons and protons. As their name suggests, neutrons are neutral from a point of view Electric. The protons are positively charged.