Covalent Bonding Notes2

Covalent bonding
What is it?
Covalent bonding occurs between two non-metal atoms, which may be
the same or different elements. Both need their atoms to gain
electrons to form a full outer shell of electrons. To gain extra
electrons, the atoms share electrons to form shared electron pairs,
which are called covalent bonds.
E.g. Water H2O
Step 1: Draw the atoms with their outer shell
Step 2: Put the atoms together and check they have a full outer
Challenge: Draw dot cross diagrams for the following molecules:
Chlorine gas (Cl2),Oxygen (O2) Carbon dioxide (CO2).
Harder: Ammonia (NH3), Methane (CH4)