Download Ionic Compounds

Ionic Compounds
Molecular Compounds (Binary Covalent)
Writing Formulas
Writing Formulas
1.
1.
2.
3.
4.
Write the symbol for the cation
Cations (+) metal ion or polyatomic ion
A roman numeral after a metal denotes the its charge
Write the symbol for the anion
Anions (-) nonmetal ion or polyatomic ion
Check the oxidation numbers of each ion, if they add up
to zero, this is the formula
Use the Criss-Cross Method to determine subscripts, the
proportion of each should sum to zero
2.
Write the symbol of the first element named; if a prefix
is used then place a subscript equal to the prefix after
the symbol
Write the symbol of the second element; if a prefix is
used then place a subscript equal to the prefix after the
symbol
Naming Compounds
Naming Compounds
1.
1.
2.
2.
Write the name of cation, metal or polyatomic ion, if the
metal can hold more than one charge then place a roman
numeral after its name to denote charge
Write the name of anion, nonmetal or polyatomic ion
3.
4.
Write the name of the first element
If the symbol is followed by a subscript of 2 or more,
then use a prefix to denote the number
Write the root of the name of the second element with
the –ide ending
Use appropriate prefix to denote the number of the
second element
Ionic Characteristics
Molecular Characteristics
Contains Ions
Metal to Nonmetal
Smallest unit “Formula Unit”
High melting & boiling points
Brittle solids at room temperature
Conducts electricity when molten
Contains Molecules
Nonmetal to Nonmetal
Smallest unit “Molecule”
Relatively Low melting & boiling points
Mostly Liquids & Gases at room temperature
Non-conductive
Acidic Compounds
Compound Naming Flow Chart
HX Where X is an elemental anion ending in - ide
1) Hydrogen  Hydro
2) - ide  - ic
3) Add Acid
HCl Hydrogen Chloride
Hydrochloric acid
HX Where X is an anion ending in - ate
1) Drop Hydrogen
2) - ate  - ic
3) Add Acid
H2SO4 Hydrogen Sulfate
Sulfuric Acid
HX Where X is an anion ending in - ite
1) Drop Hydrogen
2) - ite  - ous
3) Add Acid
H2SO3 Hydrogen Sulfite
Sulfurous Acid
1. If you have an acid then it begins with H (name it as an
ionic compound with -ide, -ate or -ite ending) then name it
as an acid, if not then continue to step 2.
2. If it is composed of two elements binary, then go to step 3,
or three elements ternary, then go to step 4.
3. If metal is present, then name it as a binary ionic compound.
If not, then it is a binary molecule.
4. If it contains a polyatomic ion, then name it as an ionic
compound. If not, then it is a complex molecule.
Compound Formula Flow Chart
1. If the name ends in acid, then go to step 2. If not, then go to
step 4.
2. If the stem ends in -ous, then it comes from an -ite anion. If
not, then it ends in -ic go to step 3.
3. If the name begins in hydro-, then the anion is an -ide. If
not, then it comes from an -ate anion.
4. If all of the elements are from the non-metal (right) side of
the periodic table, then it is a molecule. If not, then it is an
ionic compound.