Remember that what is important in chemical bonding is
the outer shell of the electrons of an atom.  An electron dot
diagram is a simplified way to show all of the information
that is needed for covalent bonding.

An electron dot diagram is made of the chemical symbol
(see last chapter if you forgot) and eight spaces for the
electron spaces in the outer shell (2 for hydrogen and
helium).  Show at the right is a sample with X's to represent
the placement of the dots.
Here you see an electron dot
diagram of a diatomic hydrogen
molecule.  Notice that it has the
chemical symbol and the dots for
the electrons, but the shells are
drawn in to show you that the
electrons are shared.  If you
erase the rings you have a true
electron dot diagram.
Shown here are four typical Electron dot
diagrams.  Again, notice how the elemental
symbols are the center and the number of
electrons in the outer shell (and only the
outer shell) are shown.

Remember: The only exception to
exceptions to the eight dots are hydrogen
and helium, which only have two.
In the electron dot diagram of water shown
at the right, shows a completed molecule.  If
you remember that oxygen has six
electrons and hydrogen has one.  You can
see that when they are combined they fill all
of the outer shells of all of the atoms.
Chapter 8 - Compounds and Molecules -
Electron Dot Diagrams
Let's look at hydrogen.  Remember that the
chemical symbol for hydrogen is H, and that it
has one electron in it's outer orbit.  When you
draw an electron dot diagram for Hydrogen it
would be an H (capital of course) with one single
dot next to it.