Sodium chloride is a giant ionic lattice consisting of alternating, adjacent positively charged sodium ions and negatively charged chloride ions in a regular arrangement of rows and columns. The ions are held together in the lattice by strong ionic bonds between the oppositely charged sodium and chloride ions. These ionic bonds form when the less electronegative sodium atoms donate 1 electron to 1 chlorine atom, which is more electronegative. This way the sodium ion formed has a positive charge of +1, having lost 1 electron, and the chloride ion has a negative charge of -1, having gained 1 electron; both are now more stable with a full outer shell of 8 electrons.