Ionic Bonding

• Ionic bonding occurs between metals and non-metals when the atoms lose or gain electrons in a bid to achieve full outer shells.

• The attraction force between oppositely charged ions (cation and anion) results in an ionic bond.

• Metals tend to lose electrons to form positive ions (cations), while non-metals gain electrons to form negative ions (anions).

• The structure of ionic compounds is usually a giant ionic lattice. These lattices are regular arrangements of ions, held together by strong electrostatic forces of attraction in all directions.

• Ionic compounds usually have high melting and boiling points due to the strong forces of attraction between the ions. It takes a lot of energy to break this lattice structure.

• In a solid state, ionic compounds do not conduct electricity because the ions are fixed in position and cannot move.

• However, if ionic compounds are melted or dissolved in water, they can conduct electricity because the ions are then free to move and carry electric charge.

• The solubility of ionic compounds in water is generally high as water molecules can surround the ions and pull them out of the lattice.

• Ionic compounds are usually brittle; when a force is applied, layers of ions can shift causing ions of like charges to align and repel each other.

• The ratio of ions in an ionic compound is always in whole numbers and is determined by the charges on the ions.

• Ionic compounds form crystals with regular shapes because of their orderly arrangement of ions.

• The disparity in electronegativity between the bonding atoms is above 1.7 in ionic bonds. The non-metal with higher electronegativity strips off an electron from the metal.

• Examples of ionic compounds include Sodium Chloride (NaCl), Potassium Bromide (KBr), and Magnesium Oxide (MgO).