UNIT 5: BONDING AND
NOMENCLATURE
IONIC COMPOUNDS
Honors Chemistry
GHS
OBJECTIVES:
How do I say that?
•  Why is NaCl called “Sodium Chloride” and not
“Sodium Chlorine?”
•  Chemistry has its own language
•  Different types of compounds have different types of
names
•  Covalent
•  Ionic
•  Acids
•  Hydrates
REVIEW: Types of IONS
IONS are atoms that have lost or gained electrons, resulting
in an electric charge.
Positively charged ions (Li+) are cations.
Negatively charged ions (F-) are anions
FIRST UP: Binary Ionic Compounds
•  IONIC COMPOUNDS consist of 2 or more ions attached
together.
•  One ion (cation) gives 1 or more electrons to the other
ion (anion).
•  Usually composed of positive (+) metal cation and and
negative (-) nonmetal anions
•  Elements are not attached to one another ~ They are
bonded by transfer of electrons which creates
electrostatic attraction
Examples of Binary Ionic Compounds
Forming IONIC COMPOUNDS
POLYATOMIC MOLECULES
•  Polyatomic ions have more than one atom.
•  The GROUP of atoms carries a charge.
Examples:
F- (monatomic anion)
PO43- (polyatomic anion)
MEMORIZE THESE:
The SUBSCRIPTS indicate how many of
that ion or polyatomic ion
BINARY IONIC Compounds –
NO overall charge
•  The charges on the cation and anion cancel each other
out; the overall charge for the compound = 0
Predicting IONIC CHARGE
•  Charge on polyatomic ions are KNOWN
•  Some other charges for representative elements may be
predicted using the periodic table:
Using Roman Numerals
•  Some elements have cations with different charges
•  Transition elements
•  Charge is specified with Roman Numerals
Writing Binary Ionic Compound Names
•  Cation is written FIRST.
•  Simply the NAME of the cation!
•  Anion is written second.
•  Use first part of the name, then add “ide”
•  EXAMPLES:
You try it!
What about using polyatomic ions?
•  Cation is written FIRST.
•  Simply the NAME of the cation!
•  Anion is written second.
•  Use the NAME of the polyatomic anion!
•  EXAMPLE:
HINTS for Remembering Polyatomic Ions
•  See the handout given on nomenclature
YOU TRY IT:
Writing FORMULAS for Ionic Compounds
•  Charges must cancel out to make the
compound have no charge
•  Use multiplication OR the criss-cross method!