1. From Standard Grade
If we exclude the metal elements
There are two types of bonding
Ionic
Covalent
Covalent molecular
Covalent Network
Covalent is divided into two parts

2. Covalent Molecular
In covalent molecular bonding the atoms are joined into
discrete molecules
The molecules can be represented by simple formula
Eg. CH4 C6H12O6 C33H C60
Covalent molecular compounds tend to be gases,
Liquids or low melting point solids
Covalent molecular solids do not conduct electricity

3. Covalent Network Structure
In a covalent network the atoms are all joined in one
large 3-dimensional structure
This type of bonding is rare, examples are
Carbon as diamond
Carbon as graphite
Silicon dioxide
Silicon
All substances with covalent network bonding have
extremely high melting points
The only covalent network solid to conduct is graphite
(it can conduct because it contains delocalised electrons)

4. Ionic compounds
Ionic compound tend to be formed when metals bond to
non-metals - +
The ions formed join
together to form a
3-dimensional crystal lattice
The ions are tightly held
together and for this reason
ionic compounds do not
conduct electricity as solids

5. - + - + When melted (or dissolved) the crystal lattice is broken
and the ions are free to move - + - +
The ionic compound can
now conduct electricity
As ionic bond are strong ionic compounds are high melting point solids

6. + Metallic Bonding This is the type of bonding found in metals
Positive ions are surrounded by delocalised electrons + e-
It is these delocalised electrons which allow metals to conduct as solids
The larger the positive charge the more delocalised electrons,
which gives a stronger metallic bond