6.1.3 - Binary compounds
containing metals with variable ionic charges
In section 6.1.2 we learned that
some metals on the periodic table have fixed ionic charges. All the other metals
that are not on the list of metals with fixed ionic charges are metals
with variable ionic charges. Review the
metals with fixed ionic charges. Click on the button below to review the
fixed charges associated with these 13 metals.
Many metals on the periodic table have variable charges. For example:
the element iron, Fe, can occur as +2 ions in some compounds and can occur
as +3 ions in other compounds.
With this type of metals which can have variable charges, you
have to consider the charge associated with the metal cations.
Here are some examples of binary compounds containing metals with
variable ionic charges:
Some metal ions with variable charges have Latin names. Because
Latin names are still widely used in today's literature, we need to learn some
Latin names of a few common metal ions. In this course we will restrict to learn
the Latin names of 5 common metal ions so that if you are given a compound that
has a Latin metal name, you will be able to write the chemical formula for the
Rules for naming binary compounds containing
metals with variable ionic charges:
Determine the charge of the metal in the compound.
Name the metal followed by a Roman numeral in parentheses immediately following
the name of the metal. The Roman numeral represents the charge of the metal.
Name the nonmetal with the ending -ide.
No Greek prefixes necessary here because the charge on the metal is labelled,
therefore, in forming a compound, there is only one possible combination with
Let's apply the above rules and name the above
examples. Click on each formula to check the name of each compound.
Compounds Containing a