UEQ: How does the structure of matter influence its
physical and chemical behavior?
Concept: chemical formula
LEQ: How can the periodic table be used to
predict the products of a chemical reaction?
 Elements  compounds
 New properties are created
 Why do elements form compounds?
 To become more chemically stable by
getting a complete outer energy level.
Concept: chemical formula
LEQ: How can the periodic table be used to
predict the products of a chemical reaction?
 What are chemical formulas?
 A formula that tells you number of atoms
each element in a compound represented by
symbols and subscripts
Concept: chemical formula
LEQ: LEQ: How can the periodic table be used to
predict the products of a chemical reaction?
 Subscripts
 small numbers to the lower right of the
chemical symbol
 Represents the number of atoms of that
element present in the compound
 ***the subscript of 1 is never written in a
chemical formula because it is understood
since the chemical symbol is there****
Concept: chemical formula
LEQ: How can the periodic table be used to
predict the products of a chemical reaction?
 Looking at the following formulas state the
number of atoms for each compound.
 NH4OH
 NH4C
 Ag2O
 K2SO4
 Ca (NO3)2
 Na2S
Concept: chemical formula
LEQ: How can the periodic table be used to
predict the products of a chemical reaction?
 What are characteristics of polyatomic ions?
 Form ternary compounds (3 elements)
 Covalent molecules with a charge
 Behave as if they were one atomic ion
Concept: chemical formula
LEQ: How can the periodic table be used to
predict the products of a chemical reaction?
 What are common polyatomic ions?
 Ammonium – NH4 1+ (only positive one)
 Hydroxide – OH1 Nitrite – NO2 1 Nitrate – NO3 1 Sulfite – SO3 2-
 Sulfate – SO4 2 Carbonate – CO3 2 Phosphate - PO4 3-
Concept: chemical formula
LEQ: How can the periodic table be used to
predict the products of a chemical reaction?
 Remember, oxidation numbers tell how
many electrons and atom has gained, lost, or
shared to become stable.
 Shown as superscripts.
Concept: chemical formula
LEQ: How can the periodic table be used to
predict the products of a chemical reaction?
 We use oxidation numbers and their least
common multiples to write formulas
So, if both subscripts are divisible by the same
number, they must be reduced to have
formula in proper form.
 When writing formulas, the compound
should be neutral (same number of + and charges)
Concept: chemical formula
LEQ: What are characteristics of ionic bonding?
 Binary compounds
 Gained (anion - ) or lost (cation +) electrons
 Electrical attraction (opposite charges hold
compounds together)
 Smallest particle is an ion
 Solid at room temperature
Concept: chemical formula
LEQ: What are characteristics of ionic bonding?
 Crystalline lattice structure (repeating
patterns of ions)
 Between a metal and nonmetal
 Stronger than covalent bonds
 Formula unit
 Makes atoms more stable
 Lowers potential energy
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
How do you write the formula of a simple
ionic compound?
1. Write the ions beside each other (first cation
then anion)
2. Write the oxidation of each as superscripts w/
charge
3. Drop the +/- signs
4. Crisscross superscripts so they become
subscripts
5. Reduce when possible
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
Practice
Write the formula for the following
 Magnesium chloride
 Potassium iodide
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
Practice-Answers
 Magnesium chloride- MgCl2
 Potassium iodide- KI
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
Practice on your own
Write the formula for the following
 Boron oxide
 Beryllium and Nitrogen
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
Practice-Answers
 Boron oxide- B2O3
 Beryllium and Nitrogen – Be3N2
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
Bell Work 11/28/12
Write the formula unit for the following:
Lithium nitride
Sodium fluoride
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
 How do you write the formula of an ionic compound










with a transition metal?
Ti (4+, 3+)
Cr (2+, 3+, 6+)
Mn ( 3+, 4+, 6+)
Fe (2+, 3+)
Co (2+, 3+)
Ni (2+, 3+)
Cu (2+, 1+)
Zn (2+)
Pb (2+, 4+)
Sn (2+, 4+)
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
Practice
Write formula for the following
 Iron (III) oxide
 Zinc (II) chloride
 Silver (I) chloride
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
 Practice
 Write formula for the following
 Iron (III) oxide – Fe2 O3
 Zinc (II) chloride – Zn Cl2
 Silver (I) chloride – Ag Cl
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
Practice
Write formula for the following
 Copper (II) phosphide
 Manganese (IV) oxide
 Lead (IV) sulfide
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
 Practice
 Write formula for the following
 Copper (II) phosphide – Cu3 P2
 Manganese (IV) oxide – Mn O2
 Lead (IV) sulfide – Pb S2
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
How do you write the formula of an ionic
compound with a polyatomic ion?
 Treat the polyatomic ion as one
 Crisscross to determine formula
 Use parenthesis around polyatomic ion
 Only reduce subscripts that are outside of
the parenthesis
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
 Cation
 Anion
 Ca 2+
 NO 3 –
 Mg 2+
 PO 4 3-
 Ba 2+
 OH –
 Ba 2+
 SO 4 2-
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
Bell Work 11/29/12
Practice writing formulas with polyatomic
ions
Sodium carbonate
Calcium carbonate
Aluminum carbonate
Sodium phosphate
Calcium phosphate
Aluminum phosphate
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
Practice writing formulas with polyatomic
ions
Sodium carbonate – Na2CO3
Calcium carbonate – CaCO3
Aluminum carbonate – Al2(CO3)3
Sodium phosphate – Na3 PO4
Calcium phosphate – Ca3 (PO3)2
Aluminum phosphate – AlPO3
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
How do you name ionic compounds?
 Write metal name first
 Remember if it is a transition metal, YOU
MUST put a Roman Numeral after its name
to represent its oxidation number!!! Look at
the subscript of the nonmetal for this
information!!!
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
How do you name ionic compounds?
 Then, write the nonmetal name. Drop the
ending and add –ide to the end
 Ex. Nitride, sulfide, fluoride, oxide, bromide,
iodide, chloride, telluride, phosphide
 If it is a ternary compound; then, just write
the name of the polyatomic ion.
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
 Practice Naming Ionic Compounds
 MnO2
 Ca (NO3)2
 BaSO4
 Cu3P2
 AgCl
 B2O3
 MgCl2
 Ba (OH)2
Concept: Chemical Formulas
LEQ: What are characteristics of ionic bonding?
 Practice Naming Ionic Compounds-Answers
 MnO2 – Manganese (IV) oxide
 Ca (NO3)2 – Calcium nitrate
 BaSO4 – Barium sulfate
 Cu3P2 – Copper (II) phosphide
 AgCl – Silver (I) chloride
 B2O3 – Boron oxide
 MgCl2 – Magnesium chloride
 Ba (OH)2 – Barium hydroxide