atom is made up of three constituting particles:
1. protons: these are positively charged particles which reside in the nucleus situated at the center of an atom.
2. neutrons: these are neutral particles i.e they have no charge they contribute towards the mass of an atom. the reside in the nucleus of the atom.
3.electrons : these are negatively charged particles that revolve around the nucleus in a fixed orbit.
hope you may like it! :)
add as brainliest answer plzz..!!! ^_^