Electrons are live in shells or energy levels which numbered to 4 and have certain letters that are K, L and N. They spin around the nucleus in these shells.
Atoms are electrically neutral because the number of protons equals the number of electrons, balancing the positive and negative charges. If this balance is changed then an atom becomes charged and is an Ion. Ions form in a chemical reaction because electrons move from atom to atom. If an atom loses electrons, it becomes a positive ion.If and atom gains electrons then it becomes a negative charge.