Ionic compounds
What is an ionic compound?
An ionic compound is made up of a metal and a non-metal.
| Metal | Non metal | Ionic compound | Chemical formula |
| Sodium | Chlorine | Sodium chloride | NaCl |
| Lithium | Hydrogen | Lithium hydride | LiH |
| Magnesium | Oxygen | Magensium oxide | MgO |
| Aluminum | Oxygen | Aluminum oxide | Al2O3 |
In the formation of ionic compounds there is a transfer of electrons from a metal to a non-metal.
Metals lose electrons to produce positive ions. eg. sodium ion, Na+
Na → Na+ + e−
Non metals gain electrons producing negative ions. eg. chloride ion, Cl-
Cl + e− → Cl−
An ionic bond is the electrostatic attraction between two oppositely charged ions. eg. Na+ and Cl-
Na+ + Cl− → NaCl
Metal and non-metal ions combine with one another to produce an orderly arrangement of ions called a crystal lattice. The crystal has an overall neutral charge.
The ionic compound sodium chloride or NaCl is made up of sodium, Na+ and chloride, Cl- ions in the ratio of one to one or Na+: Cl- = 1:1
The metal sodium reacts with chlorine to produce the compound sodium chloride.
Sodium + Chlorine → Sodium chloride
Na + Cl → NaCl
In the reaction between sodium and chlorine an electron is transferred between the atoms producing oppositely charged ions. These ions are attracted to one another producing an ionic bond.
During the reaction energy is released.