iiiiiiiv ionic compounds chemical bonding. b. lewis structures zionic – show transfer of e -
TRANSCRIPT
I II III IV
Ionic Compounds
Chemical Bonding
B. Lewis Structures
Ionic – show transfer of e-
Things to know about Ionic
Ionic compounds are made up of?
The electrons are being?
What is written first?
Opposite charges will?
Oxidation Number
Oxidation number is the number of electrons an atom gains or loseswhen bonding.
This can be determined by understanding the valence electrons, and how atoms become stable.
An atom is stable when it has a complete outer energy level, typically eight valence electrons.
• Look at Boron in it’s
normal state
• Not stable! – NO
OCTET! How would
this atom become
stable?
• Gain 5 or lose 3?
• And the winner is…..
Oxidation Number
How to write Ionic Formulas
Ionic Formulas
Overall net charge must equal zero.
S.O.C.S
Symbols -> Oxidation # -> Crisscross -> Simplify
DO NOT show charges in the final formula.
Writing Formula Practice
Potassium Chloride K+ S K2S
Beryllium Sulfide Be+2 S BeS =
Reduce
Ionic Nomenclature
How to Name an Ionic Compound
Write the name of the Cation (Metal) first. It comes straight off the periodic table.
Change ending of the Anion (Nonmetal) to end in -ide.
Naming Practice
Al2O3
Aluminum Oxide
CaS
Calcium Sulfide
Polyatomic Ions
When you have a compound that has more than 2 elements, you must look at a Polyatomic Chart for help.
When writing these formulas, keep these ions in parentheses.
These ions will also have different endings (-ate) (-ite)
Use the same SOCS method for writing formulas.
Writing a Formula
You need to determine if a Polyatomic Ion is present! How?
Look at the suffix of the name. (-ATE) or (-ITE) indicates Polyatomic Ion What are some exceptions??? What if the ending is (-IDE)? (-IDE) usually indicates periodic table
element. Note exceptions!
Writing Polyatomics
Potassium Nitrate
KNO3
Aluminum Sulfide
Al2S3
Barium Phosphite
Ba3(PO3)2
Naming Polyatomics
Look for more than two elements. That’s means a Polyatomic ion is present.
Match up the polyatomic ion from the chart and copy the name and ending straight from the chart.
Practice w/ Polyatomics
CaSO4
Calcium Sulfate
Ga(IO3)3
Gallium Iodate
Writing formulas with Transition Metals
When a Transition metal is involved, you must identify which ion is bonding.
These ions have different oxidation numbers.
Look for the Roman Numeral in the name when writing the formula.
The Roman numeral is the oxidation number of the transition metal.
Practice Writing Trans
Copper (II) Fluoride CuF2
Nickel (IV) Oxide NiO2 (Simplified formula)
Naming Transitions
When naming the compound, you must balance the total charge, (It must be zero!)
Look at the Anion and Determine the total charge. (Multiply Oxidation # by subscript)
Look at the Cation. Remembering that the sum of the ionic compound must equal zero,
Determine the positive charge, and it will be the correct roman numeral.
Practice Naming Trans
Au2S
Gold(I) Sulfide ZnO Zinc (II) Oxide FeN
Iron(III) Nitride