why are all atoms neutral?

All atoms are neutral because all atoms have the same number of protons as they have electrons. Atoms are made up of a nucleus and electrons that surround their nucleus in shells. The nucleus contains protons and neutrons. Neutrons have no charge and protons have a '+1' charge. So the nucleus will have a positive charge with varying size, depending on how many protons it has. Electrons have '-1' charges and are always in equal numbers to the protons. So, the charges balance out. For every '-1' charge there is a '+1' charge.