Chemical Formulas
and Nomenclature
Chemical Formulas
Contain:
Element Symbols
Subscripts for each element
Coefficients for each formula
2 Mg(NO3)2
Coefficient
Subscript
Examples: Write the number of each
element found in the following formulas.
Mg3N2
3 CoBr2
Ni(OH)2
2 (NH4)2SO4
4 Cr2(C2O4)3
Examples: Write the number of each
element found in the following formulas.
Mg3N2 : Mg = 3, N = 2
3 CoBr2
Ni(OH)2
2 (NH4)2SO4
4 Cr2(C2O4)3
Examples: Write the number of each
element found in the following formulas.
Mg3N2 : Mg = 3, N = 2
3 CoBr2 : Co = 3, Br = 6
Ni(OH)2
2 (NH4)2SO4
4 Cr2(C2O4)3
Examples: Write the number of each
element found in the following formulas.
Mg3N2 : Mg = 3, N = 2
3 CoBr2 : Co = 3, Br = 6
Ni(OH)2 : Ni = 1, O = 2, H = 2
2 (NH4)2SO4
4 Cr2(C2O4)3
Examples: Write the number of each
element found in the following formulas.
Mg3N2 : Mg = 3, N = 2
3 CoBr2 : Co = 3, Br = 6
Ni(OH)2 : Ni = 1, O = 2, H = 2
2 (NH4)2SO4 : N = 4, H = 16, S = 2, O = 8
4 Cr2(C2O4)3
Examples: Write the number of each
element found in the following formulas.
Mg3N2 : Mg = 3, N = 2
3 CoBr2 : Co = 3, Br = 6
Ni(OH)2 : Ni = 1, O = 2, H = 2
2 (NH4)2SO4 : N = 4, H = 16, S = 2, O = 8
4 Cr2(C2O4)3 : Cr = 8, C = 24, O = 48
Naming Chemicals
(Nomenclature)
Process of naming a chemical formula is
based on its type.
Two basic types of chemical formulas:
Ionic and Covalent
Ionic: composed of a metal and a nonmetal
Covalent: composed of two non-metals
Rules for Hydrogen
If hydrogen comes first in the formula use
the ionic rules UNLESS it is bonded to
oxygen.
If hydrogen comes second in the formula
then:
 Use ionic rules if a metal is listed first.
 Use covalent first if a non-metal is listed
first.
Examples: Identify the following as Ionic or
Covalent
a. NO =
f. HI
b. CaSiO3
g. H2O
c. PbCrO4
h. KH
d. CH4
i. NH2
e. HCl
j. MoCl2
Examples: Identify the following as Ionic or
Covalent
a. NO = C
f. HI
b. CaSiO3
g. H2O
c. PbCrO4
h. KH
d. CH4
i. NH2
e. HCl
j. MoCl2
Examples: Identify the following as Ionic or
Covalent
a. NO = C
f. HI =
b. CaSiO3 = I
g. H2O =
c. PbCrO4 =
h. KH =
d. CH4 =
i. NH2 =
e. HCl =
j. MoCl2 =
Examples: Identify the following as Ionic or
Covalent
a. NO = C
f. HI =
b. CaSiO3 = I
g. H2O =
c. PbCrO4 = I
h. KH =
d. CH4 =
i. NH2 =
e. HCl =
j. MoCl2 =
Examples: Identify the following as Ionic or
Covalent
a. NO = C
f. HI =
b. CaSiO3 = I
g. H2O =
c. PbCrO4 = I
h. KH =
d. CH4 = C
i. NH2 =
e. HCl =
j. MoCl2 =
Examples: Identify the following as Ionic or
Covalent
a. NO = C
f. HI =
b. CaSiO3 = I
g. H2O =
c. PbCrO4 = I
h. KH =
d. CH4 = C
i. NH2 =
e. HCl = I
j. MoCl2 =
Examples: Identify the following as Ionic or
Covalent
a. NO = C
f. HI = I
b. CaSiO3 = I
g. H2O =
c. PbCrO4 = I
h. KH =
d. CH4 = C
i. NH2 =
e. HCl = I
j. MoCl2 =
Examples: Identify the following as Ionic or
Covalent
a. NO = C
f. HI = I
b. CaSiO3 = I
g. H2O = C
c. PbCrO4 = I
h. KH =
d. CH4 = C
i. NH2 =
e. HCl = I
j. MoCl2 =
Examples: Identify the following as Ionic or
Covalent
a. NO = C
f. HI = I
b. CaSiO3 = I
g. H2O = C
c. PbCrO4 = I
h. KH = I
d. CH4 = C
i. NH2 =
e. HCl = I
j. MoCl2 =
Examples: Identify the following as Ionic or
Covalent
a. NO = C
f. HI = I
b. CaSiO3 = I
g. H2O = C
c. PbCrO4 = I
h. KH = I
d. CH4 = C
i. NH2 = C
e. HCl = I
j. MoCl2 =
Examples: Identify the following as Ionic or
Covalent
a. NO = C
f. HI = I
b. CaSiO3 = I
g. H2O = C
c. PbCrO4 = I
h. KH = I
d. CH4 = C
i. NH2 = C
e. HCl = I
j. MoCl2 = I
Naming Ionic Compounds
Two Basic Types
Binary Compounds – made up of two
elements
Tertiary + Compounds – made up of more
than two types of elements
Naming is also based on the number of OXIDATION
NUMBERS
Oxidation number – the charge that results on the atom
when they bond
Positive – lose
eNegative – gain eElements with more than one oxidation number: must
differentiate each number in the name. Tells which type
of the atom is being used in the compound.
Depending on what an element bonds with, it may have
either a positive or a negative oxidation number.
PAY CLOSE ATTENTION TO THE SIGNS.
Ex: Chlorine +/- 1, 3, 5, 7
Naming Binary Ionic Compounds
Two Types:
Metals with only one oxidation number
Metals with more than one oxidation
number
Binary Ionic Compounds with ONE
OXIDATION NUMBER.
1. Name the first element
2. Name the second element with “IDE”
ending.
Examples: Name the following compounds.
a. NaBr
b. BaI2
c. Al2O3
d. SrCl2
e. Ag2S
Examples: Name the following compounds.
a. NaBr Sodium Bromide
b. BaI2
c. Al2O3
d. SrCl2
e. Ag2S
Examples: Name the following compounds.
a. NaBr Sodium Bromide
b. BaI2 Barium Iodide
c. Al2O3
d. SrCl2
e. Ag2S
Examples: Name the following compounds.
a. NaBr Sodium Bromide
b. BaI2 Barium Iodide
c. Al2O3 Aluminum Oxide
d. SrCl2
e. Ag2S
Examples: Name the following compounds.
a. NaBr Sodium Bromide
b. BaI2 Barium Iodide
c. Al2O3 Aluminum Oxide
d. SrCl2 Strontium Chloride
e. Ag2S
Examples: Name the following compounds.
a. NaBr Sodium Bromide
b. BaI2 Barium Iodide
c. Al2O3 Aluminum Oxide
d. SrCl2 Strontium Chloride
e. Ag2S Silver Sulfide
Differences in First and Second Position
in formula.
First position – Positive Oxidation Number
Second position – Negative Oxidation
Number
If chlorine is in the second position = -
1
Binary Ionic Compounds
with MULTIPLE OXIDATION NUMBERS
1. Name the first element followed by the specific Roman
numeral that matches the oxidation number.
DETERMINING OXIDATION NUMBERS:
- Look at the subscript of the second element.
- Look at the oxidation number of the second element.
- Multiple them together for the total charge of the second
position element.
- Charge of the second position = charge of the first
position
- Divide the total charge of the second position element
by the subscript of the first position element, make it
positive = oxidation number of first position element
1st Position 2nd Position
Element
Oxidation
Number(s)
Subscript
Charge
End
Start
Name the second element with “IDE” ending.
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
SnCl4 =
HgF2 =
MnO =
FeO =
Fe2O3 =
CuO =
CuCl =
TiBr4 =
PbI2 =
WO2 =
CrF3 =
Name the second element with “IDE” ending.
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
SnCl4 = Tin (IV) Chloride
HgF2 =
MnO =
FeO =
Fe2O3 =
CuO =
CuCl =
TiBr4 =
PbI2 =
WO2 =
CrF3 =
Name the second element with “IDE” ending.
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
SnCl4 = Tin (IV) Chloride
HgF2 = Mercury (II) Fluoride
MnO =
FeO =
Fe2O3 =
CuO =
CuCl =
TiBr4 =
PbI2 =
WO2 =
CrF3 =
Name the second element with “IDE” ending.
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
SnCl4 = Tin (IV) Chloride
HgF2 = Mercury (II) Fluoride
MnO = Manganese (II) Oxide
FeO =
Fe2O3 =
CuO =
CuCl =
TiBr4 =
PbI2 =
WO2 =
CrF3 =
Name the second element with “IDE” ending.
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
SnCl4 = Tin (IV) Chloride
HgF2 = Mercury (II) Fluoride
MnO = Manganese (II) Oxide
FeO = Iron (II) Oxide
Fe2O3 =
CuO =
CuCl =
TiBr4 =
PbI2 =
WO2 =
CrF3 =
Name the second element with “IDE” ending.
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
SnCl4 = Tin (IV) Chloride
HgF2 = Mercury (II) Fluoride
MnO = Manganese (II) Oxide
FeO = Iron (II) Oxide
Fe2O3 = Iron (III) Oxide
CuO =
CuCl =
TiBr4 =
PbI2 =
WO2 =
CrF3 =
Name the second element with “IDE” ending.
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
SnCl4 = Tin (IV) Chloride
HgF2 = Mercury (II) Fluoride
MnO = Manganese (II) Oxide
FeO = Iron (II) Oxide
Fe2O3 = Iron (III) Oxide
CuO = Copper (II) Oxide
CuCl =
TiBr4 =
PbI2 =
WO2 =
CrF3 =
Name the second element with “IDE” ending.
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
SnCl4 = Tin (IV) Chloride
HgF2 = Mercury (II) Fluoride
MnO = Manganese (II) Oxide
FeO = Iron (II) Oxide
Fe2O3 = Iron (III) Oxide
CuO = Copper (II) Oxide
CuCl = Copper (I) Chloride
TiBr4 =
PbI2 =
WO2 =
CrF3 =
Name the second element with “IDE” ending.
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
SnCl4 = Tin (IV) Chloride
HgF2 = Mercury (II) Fluoride
MnO = Manganese (II) Oxide
FeO = Iron (II) Oxide
Fe2O3 = Iron (III) Oxide
CuO = Copper (II) Oxide
CuCl = Copper (I) Chloride
TiBr4 = Titanium (IV) Bromide
PbI2 =
WO2 =
CrF3 =
Name the second element with “IDE” ending.
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
SnCl4 = Tin (IV) Chloride
HgF2 = Mercury (II) Fluoride
MnO = Manganese (II) Oxide
FeO = Iron (II) Oxide
Fe2O3 = Iron (III) Oxide
CuO = Copper (II) Oxide
CuCl = Copper (I) Chloride
TiBr4 = Titanium (IV) Bromide
PbI2 = Lead (II) Iodide
WO2 =
CrF3 =
Name the second element with “IDE” ending.
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
SnCl4 = Tin (IV) Chloride
HgF2 = Mercury (II) Fluoride
MnO = Manganese (II) Oxide
FeO = Iron (II) Oxide
Fe2O3 = Iron (III) Oxide
CuO = Copper (II) Oxide
CuCl = Copper (I) Chloride
TiBr4 = Titanium (IV) Bromide
PbI2 = Lead (II) Iodide
WO2 = Tungsten (IV) Oxide
CrF3 =
Name the second element with “IDE” ending.
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
SnCl4 = Tin (IV) Chloride
HgF2 = Mercury (II) Fluoride
MnO = Manganese (II) Oxide
FeO = Iron (II) Oxide
Fe2O3 = Iron (III) Oxide
CuO = Copper (II) Oxide
CuCl = Copper (I) Chloride
TiBr4 = Titanium (IV) Bromide
PbI2 = Lead (II) Iodide
WO2 = Tungsten (IV) Oxide
CrF3 = Chromium (III) Fluoride
Tertiary + Compounds: Compounds containing POLYATOMIC IONS
POLYATOMIC IONS: Unbalanced (electrically charged) combinations of metals and non-metals that
bond with other ions
Poly Atomic Ions
Positive Ions
Ammonium
Mercury (I)
NH4+
Hg22+
Negative Ions
Acetate
Perchlorate
Chlorate
Chlorite
Hypochlorite
Cyanide
Hydroxide
Iodate
Nitrate
Nitrite
Permanganate
Bromate
Bicarbonate
CH3COO ClO4ClO3 ClO2 ClO CNOHIO3 NO3 NO2MnO4 BrO3 HCO3-
Carbonate
Chromate
Dichromate
Peroxide
Silicate
Sulfate
Sulfite
Tetraborate
CO3 2CrO4 2Cr2O7 2O2 2SiO3 2SO4 2SO3 2B4O7 2-
Phosphate
Arsenate
PO4 3AsO4 3-
First Position Metals with One Oxidation
Number + Polyatomic Ions
1. Name the metal in first position.
2. Name the polyatomic ion in the
second position
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
CaSO4
MgCO3
KClO
Sr(NO3)2
Na3PO4
Ag2CO3
BaCrO4
K2MnO4
Al2(SO3)3
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
CaSO4 = Calcium Sulfate
MgCO3
KClO
Sr(NO3)2
Na3PO4
Ag2CO3
BaCrO4
K2MnO4
Al2(SO3)3
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
CaSO4 = Calcium Sulfate
MgCO3 = Magnesium Carbonate
KClO
Sr(NO3)2
Na3PO4
Ag2CO3
BaCrO4
K2MnO4
Al2(SO3)3
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
CaSO4 = Calcium Sulfate
MgCO3 = Magnesium Carbonate
KClO = Potassium Hypochlorite
Sr(NO3)2
Na3PO4
Ag2CO3
BaCrO4
K2MnO4
Al2(SO3)3
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
CaSO4 = Calcium Sulfate
MgCO3 = Magnesium Carbonate
KClO = Potassium Hypochlorite
Sr(NO3)2 = Strontium Nitrate
Na3PO4
Ag2CO3
BaCrO4
K2MnO4
Al2(SO3)3
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
CaSO4 = Calcium Sulfate
MgCO3 = Magnesium Carbonate
KClO = Potassium Hypochlorite
Sr(NO3)2 = Strontium Nitrate
Na3PO4 = Sodium Phosphate
Ag2CO3
BaCrO4
K2MnO4
Al2(SO3)3
Examples: Name the following compounds.
a.
b.
c.
d.
e.
f.
g.
h.
i.
CaSO4 = Calcium Sulfate
MgCO3 = Magnesium Carbonate
KClO = Potassium Hypochlorite
Sr(NO3)2 = Strontium Nitrate
Na3PO4 = Sodium Phosphate
Ag2CO3 = Silver Carbonate
BaCrO4
K2MnO4
Al2(SO3)3
Examples: Name the following compounds.
a.
CaSO4 = Calcium Sulfate
b.
MgCO3 = Magnesium Carbonate
c.
KClO = Potassium Hypochlorite
d.
Sr(NO3)2 = Strontium Nitrate
e.
Na3PO4 = Sodium Phosphate
f.
Ag2CO3 = Silver Carbonate
g.
BaCrO4 = Barium Chromate
h.
K2MnO4
i.
Al2(SO3)3
Examples: Name the following compounds.
a.
CaSO4 = Calcium Sulfate
b.
MgCO3 = Magnesium Carbonate
c.
KClO = Potassium Hypochlorite
d.
Sr(NO3)2 = Strontium Nitrate
e.
Na3PO4 = Sodium Phosphate
f.
Ag2CO3 = Silver Carbonate
g.
BaCrO4 = Barium Chromate
h.
K2MnO4 = Potassium Permanganate
i.
Al2(SO3)3
Examples: Name the following compounds.
a.
CaSO4 = Calcium Sulfate
b.
MgCO3 = Magnesium Carbonate
c.
KClO = Potassium Hypochlorite
d.
Sr(NO3)2 = Strontium Nitrate
e.
Na3PO4 = Sodium Phosphate
f.
Ag2CO3 = Silver Carbonate
g.
BaCrO4 = Barium Chromate
h.
KMnO4 = Potassium Permanganate
i.
Al2(SO3)3 = Aluminum Sulfite
First Position Metals with Multiple Oxidation Numbers
+ Polyatomic Ions
1. Name the first element followed by the specific
Roman numeral that matches the oxidation number.
2. Name the polyatomic ion in the second position
Examples: Name the following compounds.
a. Pb(NO3)2
b. CuClO4
c. Hg(CN)2
d. CoCO3
e. CrBr3
First Position Metals with Multiple Oxidation Numbers
+ Polyatomic Ions
1. Name the first element followed by the specific
Roman numeral that matches the oxidation number.
2. Name the polyatomic ion in the second position
Examples: Name the following compounds.
a. Pb(NO3)2 = Lead (II) Nitrate
b. CuClO4
c. Hg(CN)2
d. CoCO3
e. CrBr3
First Position Metals with Multiple Oxidation Numbers
+ Polyatomic Ions
1. Name the first element followed by the specific
Roman numeral that matches the oxidation number.
2. Name the polyatomic ion in the second position
Examples: Name the following compounds.
a. Pb(NO3)2 = Lead (II) Nitrate
b. CuClO4 = Copper (I) Perchlorate
c. Hg(CN)2
d. CoCO3
e. CrBr3
First Position Metals with Multiple Oxidation Numbers
+ Polyatomic Ions
1. Name the first element followed by the specific
Roman numeral that matches the oxidation number.
2. Name the polyatomic ion in the second position
Examples: Name the following compounds.
a. Pb(NO3)2 = Lead (II) Nitrate
b. CuClO4 = Copper (I) Perchlorate
c. Hg(CN)2 = Mercury (II) Cyanide
d. CoCO3
e. CrBr3
First Position Metals with Multiple Oxidation Numbers
+ Polyatomic Ions
1. Name the first element followed by the specific
Roman numeral that matches the oxidation number.
2. Name the polyatomic ion in the second position
Examples: Name the following compounds.
a. Pb(NO3)2 = Lead (II) Nitrate
b. CuClO4 = Copper (I) Perchlorate
c. Hg(CN)2 = Mercury (II) Cyanide
d. CoCO3 = Cobalt (II) Carbonate
e. CrBr3
First Position Metals with Multiple Oxidation Numbers
+ Polyatomic Ions
1. Name the first element followed by the specific
Roman numeral that matches the oxidation number.
2. Name the polyatomic ion in the second position
Examples: Name the following compounds.
a. Pb(NO3)2 = Lead (II) Nitrate
b. CuClO4 = Copper (I) Perchlorate
c. Hg(CN)2 = Mercury (II) Cyanide
d. CoCO3 = Cobalt (II) Carbonate
e. CrBr3 = Chromium (III) Bromide
Polyatomic Ions in the First Position
Name the polyatomic ion in the first position.
Name the element in the second position with
“IDE” ending OR name the polyatomic ion in
the second position.
Example: Name the following compounds.
a.
b.
c.
d.
e.
NH4Cl
(NH4)2Cr2O7
Hg2CO3
NH4CH3COO
NH4NO3
Polyatomic Ions in the First Position
Name the polyatomic ion in the first position.
Name the element in the second position with
“IDE” ending OR name the polyatomic ion in
the second position.
Example: Name the following compounds.
a.
b.
c.
d.
e.
(NH4)Cl = Ammonium Chloride
(NH4)2Cr2O7
Hg2CO3
NH4CH3COO
NH4NO3
Polyatomic Ions in the First Position
Name the polyatomic ion in the first position.
Name the element in the second position with
“IDE” ending OR name the polyatomic ion in
the second position.
Example: Name the following compounds.
a.
b.
c.
d.
e.
(NH4)Cl = Ammonium Chloride
(NH4)2Cr2O7 = Ammonium Dichromate
Hg2CO3
NH4CH3COO
NH4NO3
Polyatomic Ions in the First Position
Name the polyatomic ion in the first position.
Name the element in the second position with
“IDE” ending OR name the polyatomic ion in
the second position.
Example: Name the following compounds.
a.
b.
c.
d.
e.
(NH4)Cl = Ammonium Chloride
(NH4)2Cr2O7 = Ammonium Dichromate
Hg2CO3 = Mercury (I) Carbonate
NH4CH3COO
NH4NO3
Polyatomic Ions in the First Position
Name the polyatomic ion in the first position.
Name the element in the second position with
“IDE” ending OR name the polyatomic ion in
the second position.
Example: Name the following compounds.
a.
b.
c.
d.
e.
(NH4)Cl = Ammonium Chloride
(NH4)2Cr2O7 = Ammonium Dichromate
Hg2CO3 = Mercury (I) Carbonate
NH4CH3COO = Ammonium Acetate
NH4NO3 = Ammonium Nitrate
Special Cases in Ionic Nomenclature = Acids
While all acids can be named using the ionic methods, it is
common practice to give them common names.
Examples:
HCH3COO =
HF =
HCl =
H3PO4 =
HNO3 =
H2SO4 =
Special Cases in Ionic Nomenclature = Acids
While all acids can be named using the ionic methods, it is
common practice to give them common names.
Examples:
HCH3COO = Acetic Acid
HF =
HCl =
H3PO4 =
HNO3 =
H2SO4 =
Special Cases in Ionic Nomenclature = Acids
While all acids can be named using the ionic methods, it is
common practice to give them common names.
Examples:
HCH3COO = Acetic Acid
HF = Hydrofluoric Acid
HCl =
H3PO4 =
HNO3 =
H2SO4 =
Special Cases in Ionic Nomenclature = Acids
While all acids can be named using the ionic methods, it is
common practice to give them common names.
Examples:
HCH3COO = Acetic Acid
HF = Hydrofluoric Acid
HCl = Hydrochloric Acid
H3PO4 =
HNO3 =
H2SO4 =
Special Cases in Ionic Nomenclature = Acids
While all acids can be named using the ionic methods, it is
common practice to give them common names.
Examples:
HCH3COO = Acetic Acid
HF = Hydrofluoric Acid
HCl = Hydrochloric Acid
H3PO4 = Phosphoric Acid
HNO3 =
H2SO4 =
Special Cases in Ionic Nomenclature = Acids
While all acids can be named using the ionic methods, it is
common practice to give them common names.
Examples:
HCH3COO = Acetic Acid
HF = Hydrofluoric Acid
HCl = Hydrochloric Acid
H3PO4 = Phosphoric Acid
HNO3 = Nitric Acid
H2SO4 =
Special Cases in Ionic Nomenclature = Acids
While all acids can be named using the ionic methods, it is common
practice to give them common names.
Examples:
HCH3COO = Acetic Acid
HF = Hydrofluoric Acid
HCl = Hydrochloric Acid
H3PO4 = Phosphoric Acid
HNO3 = Nitric Acid
H2SO4 = Sulfuric Acid
!!!!!!MEMORIZE THESE!!!!!!!
NAMING COVALENT MOLECULES
Binary Molecules – Two Non-Metals
Use Greek Prefixes to designate the subscripts of each
type of atom in the molecule.
Subscript
Prefix
1
Mono
2
Di
3
Tri
4
Tetra
5
Penta
6
Hexa
7
Hepta
8
Octa
9
Nona
10
Deca
1. Write the name of the Greek prefix before
the name of the element. Prefix is based
on the subscript.
EXCEPTION: When dealing with the first
element, do not use “MONO”.
2. Add “IDE” to the end of the second
element.
Examples: Name the following molecules.
a.
b.
c.
d.
e.
CO =
CO2
P2O5
CCl4
SeO3
Examples: Name the following molecules.
a.
b.
c.
d.
e.
CO = Carbon Monoxide
CO2
P2O5
CCl4
SeO3
Examples: Name the following molecules.
a.
b.
c.
d.
e.
CO = Carbon Monoxide
CO2 = Carbon Dioxide
P2O5
CCl4
SeO3
Examples: Name the following molecules.
a.
b.
c.
d.
e.
CO = Carbon Monoxide
CO2 = Carbon Dioxide
P2O5 = Diphosphorous Pentoxide or
Pentaoxide
CCl4
SeO3
Examples: Name the following molecules.
a.
b.
c.
d.
e.
CO = Carbon Monoxide
CO2 = Carbon Dioxide
P2O5 = Diphosphorous Pentoxide or
Pentaoxide
CCl4 = Carbon Tetrachloride
SeO3
Examples: Name the following molecules.
a.
b.
c.
d.
e.
CO = Carbon Monoxide
CO2 = Carbon Dioxide
P2O5 = Diphosphorous Pentoxide or
Pentaoxide
CCl4 = Carbon Tetrachloride
SeO3 = Selenium Trioxide
Covalent Exceptions:
Nitrogen and Sulfur Bonded to Oxygen
Nitrogen Oxygen and Sulfur Oxygen molecules can either
be named using the covalent rules or with Roman
numerals.
Examples: Name the following molecules using both
the covalent method and the ionic methods.
a. NO2 =
b. SO2
c. N2O3
d. SO3
e. N2O5
Special Cases: Organic Nomenclature – a whole new set
of rules. Later
Covalent Exceptions:
Nitrogen and Sulfur Bonded to Oxygen
Nitrogen Oxygen and Sulfur Oxygen molecules can either
be named using the covalent rules or with Roman
numerals.
Examples: Name the following molecules using both
the covalent method and the ionic methods.
a. NO2 = Nitrogen Dioxide OR Nitrogen (IV) Oxide
b. SO2
c. N2O3
d. SO3
e. N2O5
Special Cases: Organic Nomenclature – a whole new set
of rules. Later
Covalent Exceptions:
Nitrogen and Sulfur Bonded to Oxygen
Nitrogen Oxygen and Sulfur Oxygen molecules can either
be named using the covalent rules or with Roman
numerals.
Examples: Name the following molecules using both
the covalent method and the ionic methods.
a. NO2 = Nitrogen Dioxide OR Nitrogen (IV) Oxide
b. SO2 = Sulfur Dioxide OR Sulfur (IV) Oxide
c. N2O3
d. SO3
e. N2O5
Special Cases: Organic Nomenclature – a whole new set
of rules. Later
Covalent Exceptions:
Nitrogen and Sulfur Bonded to Oxygen
Nitrogen Oxygen and Sulfur Oxygen molecules can either
be named using the covalent rules or with Roman
numerals.
Examples: Name the following molecules using both
the covalent method and the ionic methods.
a. NO2 = Nitrogen Dioxide OR Nitrogen (IV) Oxide
b. SO2 = Sulfur Dioxide OR Sulfur (IV) Oxide
c. N2O3 = Dinitrogen Trioxide OR Nitrogen (III) Oxide
d. SO3
e. N2O5
Special Cases: Organic Nomenclature – a whole new set
of rules. Later
Covalent Exceptions:
Nitrogen and Sulfur Bonded to Oxygen
Nitrogen Oxygen and Sulfur Oxygen molecules can either
be named using the covalent rules or with Roman
numerals.
Examples: Name the following molecules using both
the covalent method and the ionic methods.
a. NO2 = Nitrogen Dioxide OR Nitrogen (IV) Oxide
b. SO2 = Sulfur Dioxide OR Sulfur (IV) Oxide
c. N2O3 = Dinitrogen Trioxide OR Nitrogen (III) Oxide
d. SO3 = Sulfur Trioxide OR Sulfur (VI) Oxide
e. N2O5 =
Special Cases: Organic Nomenclature – a whole new set
of rules. Later
Covalent Exceptions:
Nitrogen and Sulfur Bonded to Oxygen
Nitrogen Oxygen and Sulfur Oxygen molecules can either
be named using the covalent rules or with Roman
numerals.
Examples: Name the following molecules using both
the covalent method and the ionic methods.
a. NO2 = Nitrogen Dioxide OR Nitrogen (IV) Oxide
b. SO2 = Sulfur Dioxide OR Sulfur (IV) Oxide
c. N2O3 = Dinitrogen Trioxide OR Nitrogen (III) Oxide
d. SO3 = Sulfur Trioxide OR Sulfur (VI) Oxide
e. N2O5 = Dinitrogen Pentaoxide OR Nitrogen (V) Oxide
Special Cases: Organic Nomenclature – a whole new set
of rules. Later
WRITING CHEMICAL FORMULAS
Chemical compounds and molecules have
balanced charges. Therefore the subscripts and
the oxidation numbers will be used to give
balanced charges for the elements in the first
and second positions.
Example: Write the number of each atom that
will give balanced charges.
a. H
O
=
b. Ca
O
=
c. Al
O
=
WRITING CHEMICAL FORMULAS
Chemical compounds and molecules have
balanced charges. Therefore the subscripts and
the oxidation numbers will be used to give
balanced charges for the elements in the first
and second positions.
Example: Write the number of each atom that
will give balanced charges.
a. H = +1
O = -2
=
b. Ca
O
=
c. Al
O
=
WRITING CHEMICAL FORMULAS
Chemical compounds and molecules have
balanced charges. Therefore the subscripts and
the oxidation numbers will be used to give
balanced charges for the elements in the first
and second positions.
Example: Write the number of each atom that
will give balanced charges.
a. H = +1
O = -2
= H2O
b. Ca
O
=
c. Al
O
=
WRITING CHEMICAL FORMULAS
Chemical compounds and molecules have
balanced charges. Therefore the subscripts and
the oxidation numbers will be used to give
balanced charges for the elements in the first
and second positions.
Example: Write the number of each atom that
will give balanced charges.
a. H = +1
O = -2
= H2O
b. Ca = +2
O = -2
=
c. Al
O
=
WRITING CHEMICAL FORMULAS
Chemical compounds and molecules have
balanced charges. Therefore the subscripts and
the oxidation numbers will be used to give
balanced charges for the elements in the first
and second positions.
Example: Write the number of each atom that
will give balanced charges.
a. H = +1
O = -2
= H2O
b. Ca = +2
O = -2
= CaO
c. Al
O
=
WRITING CHEMICAL FORMULAS
Chemical compounds and molecules have
balanced charges. Therefore the subscripts and
the oxidation numbers will be used to give
balanced charges for the elements in the first
and second positions.
Example: Write the number of each atom that
will give balanced charges.
a. H = +1
O = -2
= H2O
b. Ca = +2
O = -2
= CaO
c. Al = +3
O = -2
=
WRITING CHEMICAL FORMULAS
Chemical compounds and molecules have
balanced charges. Therefore the subscripts and
the oxidation numbers will be used to give
balanced charges for the elements in the first
and second positions.
Example: Write the number of each atom that
will give balanced charges.
a. H = +1
O = -2
= H2O
b. Ca = +2
O = -2
= CaO
c. Al = +3
O = -2
= Al2O3
Chemical formulas are based on the names and
composition.
1. Write down the elements and polyatomic ions involved.
2. Does the name give you any clues?
- Roman numerals  oxidation number of metal
- Prefixes  Subscripts
3. If the formula is ionic, write the oxidation numbers for the
elements or polyatomic ions.
4. Determine the ratio of the elements/ions in the first and
second position so that the charges cancel each other.
5. Use the ratio as the subscripts for the
elements/polyatomic ions.
- If more than one polyatomic ion is in the formula, use
parentheses around the ions with the subscript outside
of the parentheses.
Examples: Write the chemical equations for the
following chemicals.
a. Sulfur hexafluoride
b. Ammonium Sulfate
c. Calcium Chloride
d. Lithium Nitrate
e. Carbon Tetrabromide
f. Molybdenum (IV) Hypochlorite
Examples: Write the chemical equations for the
following chemicals.
a. Sulfur hexafluoride = SF6
b. Ammonium Sulfate
c. Calcium Chloride
d. Lithium Nitrate
e. Carbon Tetrabromide
f. Molybdenum (IV) Hypochlorite
Examples: Write the chemical equations for the
following chemicals.
a. Sulfur hexafluoride = SF6
b. Ammonium Sulfate = (NH4)2SO4
c. Calcium Chloride
d. Lithium Nitrate
e. Carbon Tetrabromide
f. Molybdenum (IV) Hypochlorite
Examples: Write the chemical equations for the
following chemicals.
a. Sulfur hexafluoride = SF6
b. Ammonium Sulfate = (NH4)2SO4
c. Calcium Chloride = CaCl2
d. Lithium Nitrate
e. Carbon Tetrabromide
f. Molybdenum (IV) Hypochlorite
Examples: Write the chemical equations for the
following chemicals.
a. Sulfur hexafluoride = SF6
b. Ammonium Sulfate = (NH4)2SO4
c. Calcium Chloride = CaCl2
d. Lithium Nitrate = LiNO3
e. Carbon Tetrabromide
f. Molybdenum (IV) Hypochlorite
Examples: Write the chemical equations for the
following chemicals.
a. Sulfur hexafluoride = SF6
b. Ammonium Sulfate = (NH4)2SO4
c. Calcium Chloride = CaCl2
d. Lithium Nitrate = LiNO3
e. Carbon Tetrabromide = CBr4
f. Molybdenum (IV) Hypochlorite
Examples: Write the chemical equations for the
following chemicals.
a. Sulfur hexafluoride = SF6
b. Ammonium Sulfate = (NH4)2SO4
c. Calcium Chloride = CaCl2
d. Lithium Nitrate = LiNO3
e. Carbon Tetrabromide = CBr4
f. Molybdenum (IV) Hypochlorite = Mo(ClO)4
g. Zirconium Phosphate
h. Dihydrogen Monoxide
i. Cobalt (III) Iodide
j. Lead (II) Chromate
k. Potassium Carbonate
l. Silver Cyanide
m. Silicon Dioxide
g. Zirconium Phosphate = Zr3(PO4)4
h. Dihydrogen Monoxide
i. Cobalt (III) Iodide
j. Lead (II) Chromate
k. Potassium Carbonate
l. Silver Cyanide
m. Silicon Dioxide
g. Zirconium Phosphate = Zr3(PO4)4
h. Dihydrogen Monoxide = H2O
i. Cobalt (III) Iodide
j. Lead (II) Chromate
k. Potassium Carbonate
l. Silver Cyanide
m. Silicon Dioxide
g. Zirconium Phosphate = Zr3(PO4)4
h. Dihydrogen Monoxide = H2O
i. Cobalt (III) Iodide = CoI3
j. Lead (II) Chromate
k. Potassium Carbonate
l. Silver Cyanide
m. Silicon Dioxide
g. Zirconium Phosphate = Zr3(PO4)4
h. Dihydrogen Monoxide = H2O
i. Cobalt (III) Iodide = CoI3
j. Lead (II) Chromate = PbCrO4
k. Potassium Carbonate
l. Silver Cyanide
m. Silicon Dioxide
g. Zirconium Phosphate = Zr3(PO4)4
h. Dihydrogen Monoxide = H2O
i. Cobalt (III) Iodide = CoI3
j. Lead (II) Chromate = PbCrO4
k. Potassium Carbonate = K2CO3
l. Silver Cyanide
m. Silicon Dioxide
g. Zirconium Phosphate = Zr3(PO4)4
h. Dihydrogen Monoxide = H2O
i. Cobalt (III) Iodide = CoI3
j. Lead (II) Chromate = PbCrO4
k. Potassium Carbonate = K2CO3
l. Silver Cyanide = AgCN
m. Silicon Dioxide
g. Zirconium Phosphate = Zr3(PO4)4
h. Dihydrogen Monoxide = H2O
i. Cobalt (III) Iodide = CoI3
j. Lead (II) Chromate = PbCrO4
k. Potassium Carbonate = K2CO3
l. Silver Cyanide = AgCN
m. Silicon Dioxide = SiO2