EXAMPLE 3.3 Writing the Lewis structure of a molecule or an ion
When you are assessing the properties of a compound, such as its ability to take part
in specifi c kinds of reactions, you need to know whether the best description of a molecule
is in terms of single or multiple bonds.
Write the Lewis structures of (a) water, H2O; (b) methanal, H2CO; and (c) the
chlorite ion, ClO2
. Use the rules in Toolbox 3.1; note that you must add one electron
for the negative charge of ClO2
.
ANTICIPATE It is hard to anticipate Lewis structures when you are starting out in
your studies, but as you gain experience, you will be able to write them down without
going through the systematic procedure used here.
PLAN Go through the steps set out in the Toolbox.