Bonding

Bonding of Atoms

This is a revision concept collection of past concepts, such as ionic bonding and covalent bonding.

Ionic Bonds

For background information, see Ions.

• An ionic bond is an electrostatic force of attraction between oppositely charged ions.
  • e.g. $Mg+O\to M{g}^{2+}+O^{2-}$
• Ionic bonding only applies between metals and non-metals.

Ionic Lattices

• Ionic compounds form giant ionic lattices.
• This can be represented using the “ball and stick” model.
• An ionic bond works in all directions and can exist between many ions.

Limitations of Models

• Models are designed to provide a representation of something we can’t directly observe, and isn’t always perfect.

Covalent Bonds

• Covalent bonds are a type of bond that hold the atoms that make up molecules or compounds. They are the strong electromagnetic attraction between a shared pair of electrons and the nuclei of the bonded atoms.
  • They are formed by the sharing of valence electrons that allow the formation of full valence shells.
    • For example, a molecule such as $H_2$ is bonded by the sharing of electron from each hydrogen atom to achieve a full valence shell for both hydrogen atoms.
    • In a compound like $H_{2}O$, hydrogen will share their outer shells with oxygen to achieve a full valence shell.
    • Unlike ionic bonds, they do not lose or gain electrons but rather share them.
  • Covalent bonds can be easily remember by remembering the meaning of covalent
    • Co → cooperative
    • Valent → valence electrons