Chapter 6
Nomenclature of
Inorganic Compounds
Objectives:
Distinguish between common and systematic names of
compounds
Review differences between elements and ions
Be able to write formula from names of compounds
Understand binary compounds
Name compounds containing polyatomic ions
Name and recognize acids
Common and Systematic Names
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Common Names
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Arbitrary
Not based on chemical composition
Historically associated with a physical or chemical
property
Not consistent among languages or disciplines
Systematic names
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Identify the chemical composition
Devised by IUPAC
Elements and Ions
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Diatomic molecules
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Polyatomic
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2 atoms of same element
H2, O2, N2, F2, Cl2, Br2, I2
3 or more atoms of same element
Sulfur (S8) and Phosphorus (P4)
Ion
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Charged particle
Positive (cation)
Negative (anion)
Elements and Ions
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Naming cations
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Naming anions
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Same as element but add the word ion
Potassium ion
Stem of the parent name with ending changed to –
ide
Add the word ion
Oxide ion
Commonly formed ions – figure 6.2 pg 107
Writing Formulas from Names of
Compounds
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Chemical compounds must have a net charge
of zero
Compare charges of ions formed from
elements
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“Trade” charges and rewrite as subscript on
opposite ion
Write with lowest possible whole numbers
Writing Formulas from Names of
Compounds
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Write formulas for
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Sodium and chlorine
Na1+
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Cl1-
NaCl
Aluminum and oxygen
Al3+
O2-
Al2O3
Writing Formulas from Names of
Compounds
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Write formulas for the following
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Calcium chloride
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Calcium will form Ca2+
Chlorine will form Cl1Formula is CaCl2
Magnesium oxide
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Magnesium will form Mg2+
Oxygen will form O2-
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Formula is MgO
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Writing Formulas from Names of
Compounds
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Barium phosphide
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Barium will form Ba2+
Phosphorus will form P3-
Formula is Ba3P2
Sodium sulfide
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Sodium will form Na+
Sulfur will form S2Formula is Na2S
Binary Compounds
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Contain only two different elements
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Often metal with nonmetal (binary
ionic compound)
Binary Ionic Compounds
Containing a Metal Forming
Only One Type of Cation
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Name of cation is left the same
Name of anion is changed (-ide)
Write formulas for the following compounds
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Strontium chloride
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Strontium is Sr2+ and Chlorine is Cl-
SrCl2
Calcium sulfide
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Calcium is Ca2+ and Sulfur is S2-
CaS
Binary Ionic Compounds Containing
a Metal That Can Form Two or More
Types of Cations
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Metals in the center of the periodic table
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Stock System
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Iron can be Fe2+ or Fe3+
Use Roman Numeral to designate charge of cation
Copper (II) Chloride is CuCl2
Tin (IV) Oxide is SnO2
-ous and –ic endings are also sometimes used
Binary Ionic Compounds Containing
a Metal That Can Form Two or More
Types of Cations
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Write the name for each of the following
compounds
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PbI2
Fe2O3
CuO
TiF4
Lead (II) Iodide
Iron (III) Oxide
Copper (II) Oxide
Titanium (IV) Fluoride
Binary Compounds Containing
Two Nonmetals
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Not ionic bonds - Molecular (covalent)
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Different system of naming
Element that occurs first in the series below is
written and named first
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Si, B, P, H, C, S, I, Br, N, Cl, O, F
Usually given to you…first element listed always
named first
Second element retains –ide ending
Binary Compounds Containing
Two Nonmetals
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Prefix is attached to each element to indicate the
number of atoms of that element in the molecule
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Mono (1) never used for first element
Prefix
Meaning
Prefix
Meaning
Mono
1
Hexa
6
Di
2
Hepta
7
Tri
3
Octa
8
Tetra
4
Nona
9
Penta
5
Deca
10
Binary Compounds Containing
Two Nonmetals
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Examples:
N2O is dinitrogen monoxide (drop “o”)
 S2F10 is disulfur decofluoride
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You try:
P2O5
 CBr4
 NH3
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Diphosphorus pentoxide
Carbon tetrabromide
Nitrogen trihydride
Acids Derived from Binary
Compounds
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Hydrogen compounds – form acids in water
Write symbol of H first, then the rest
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Shows it is an acid
Naming
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Take stem of nonmetal
Add prefix hydroAdd suffix –ic
Add the word acid
Acids Derived from Binary
Compounds
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H2S
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Hydrogen sulfide (if not in water)
Hydrosulfuric acid
HCl
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Hydrogen chloride (if not in water)
Hydrochloric acid
Figure 6.4 on page 115
VERY HELPFUL FOR NAMING BINARY COMPOUNDS
Naming Compounds Containing
Polyatomic Ions
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Polyatomic ion
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Must be able to recognize common polyatomic
ions
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Table 6.6 (pg 116)
Naming Compounds Containing
Polyatomic Ions
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Usually end in –ate or –ite (but not always)
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ClO- hypochlorite
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ClO2- chlorite
-ate indicates
-ite indicates
Nitrate is NO3
Nitrite is NO2-
ClO3- chlorate
-
Hypo
(if more than two varieties)
ClO4- hyperchlorate
or perchlorate
Naming Compounds Containing
Polyatomic Ions
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Need to recognize polyatomic ions in Table 6.6
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Hydroxide (OH-)
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Cyanide (CN-)
Naming Compounds Containing
Polyatomic Ions
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Naming follows binary compound rules
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Naming Acids
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Oxy-acids
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Inorganic compounds containing hydrogen,
oxygen, and one other element
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Change ending of polyatomic ion
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Add the word “acid”
HC2H3O2
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Hydrogen & acetate ion
Acetic acid
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Homework
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Questions #1,3,6
Paired Exercises #7-25 odd
Additional Exercise #34 & 36
Remember: Quiz next class 