Ions are electrically charged particles formed when atoms lose or gain electrons. They have the same electronic structures as noble gases.
Metal atoms form positive ions, while non-metal atoms form negative ions. The strong electrostatic forces of attraction between oppositely charged ions are called ionic bonds.
Ionic compounds have high melting and boiling points.
How ions formIons are electrically charged particles formed when atoms lose or gain electrons. This loss or gain leaves a complete highest energy level, so the electronic structure of an ion is the same as that of a noble gas - such as a helium, neon or argon.
Metal atoms and non-metal atoms go in opposite directions when they ionise: