Year 9 Chemistry Ms. Benson
Covalent Bonding
Chemical bonding involves the electrons in the outer shells, the valence electrons. Whatever type of bonding holds the structure together it is only the outer electrons that are used.
Covalent Bonding:
Non-metallic elements are held together by covalent bonding (elements to the right side of the periodic table).
Covalent bonding can result in simple molecules or giant molecular lattices.
Covalent bonding is driven by the atom wanting to have a full outer electron shell (octet rule).
Non-metals need one or more electrons to fill the outer electron shell. The atoms share electrons, the orbital’s overlap, so that both achieve a full outer electron shell and stability.
The bond is formed by the sharing of a pair of electrons between two atoms.
Molecules are formed by atoms joining together by covalent bonds.
Example: Only outer electron shell shown
1. State whether you would expect the following compounds to be joined by covalent or ionic bonding?
a. Carbon dioxide b. Iron oxide c. Chlorine
d. Aluminum Chloride e. Potassium nitride
2. Draw covalent bonding for the following compounds:
a. CCl4
b. HCl
Year 9 Chemistry Ms. Benson c.
Water, H2O3. Double and triple bonds
Some atoms can bond together by sharing two or three pairs of electrons to make double or triple bonds.
Example: Oxygen has the electron configuration 2,6. It needs to gain 2 electrons. If it bonds with another oxygen atom both atoms need to gain 2 electrons. So two pairs of electrons are shared and two covalent bonds are formed.
Draw the covalent bonding for the following molecules;
N2
CO2
