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