Atoms are made of particles called electrons, protons, and neutrons. The protons, each of which carries a positive charge, are located in the nucleus of the atoms, as are the neutrons, which have no charge. The electrons, which are negatively charged, move around the outside of the nucleus in areas called orbitals.
Because the electrons are on the outside fo the atom, they can easily move around. When an atom loses an electron, it loses one unit of negative charge, but it still has all of its positively charged protons tucked away in the nucleus, so the whole atom becomes positively charged. We call a positive atom a cation; you give a number (+1, +2, +3, etc) to show its charge, which also tells you how many electrons it lost.
An atom that gains electrons becomes an anion, and has a negative charge; again the charge (-1, -2, -3) tells you how many electrons it gained. The exact number of electrons lost or gained is determined by the way the electrons are organized in the orbitals. Usually an atom that becomes an ion does so because that configuration is more stable.
so ion is atom with one electron less or more...........
am i right?
An ion is an atom or bonded group of atoms with a positive or negative charge. The charge itself is whether something is positive or negative.