Chapter 4 Nomenclature
Naming Binary Compounds (p.94 – p.116)
Binary Ionic Compound – A two-element compound consisting of a cation and an anion.
Type I Na→Na+ Cs→Cs2+ Ca→Ca2+ Al→Al3+
Type II Cr→Cr2+ or Cr→Cr3+ Cu→Cu+ or Cu→Cu2+
Type I binary compounds: The metals present form only one type of cation (p.94)
Type II binary compounds: The metals present can form two (or more) cations that have different charges. (p.94)
Type III binary compounds contain only nonmetals (p.103)
Table 4.1 (p.95) Common Simple Cation and Anions
Cation Name Anion Name______
H+ hydrogen H- hydride
Li+ lithium F- fluoride
Na+ sodium Cl- chloride
K+ potassium Br- bromide
Cs+ cesium I- iodide
Be2+ beryllium O2- oxide
Mg2+ magnesium S2- sulfide
Ca2+ calcium
Ba2+ barium
Al3+ aluminum
Ag+ silver
Zn2+ zinc
p.95 Rules for Naming Type I Ionic Compounds
1. The cation is always names first and the anion second
2. A simple cation (obtained from a single atom) takes it name from the name of the element. For example, Na+ is called sodium in the names of compounds containing this ion.
3. A simple anion (obtained form a single atom) is named by taking the first part of the element name (the root) and adding –ide. Thus the Cl- ion is called chloride.
4. Write the name for the compound by combining the names of the ion.
Examples of Binary Ionic Compounds
Compound Ions Present Name______
NaCl Na+, Cl- sodium chloride
KI K+, I- potassium iodide
CaS Ca2+, S2- calcium sulfide
CsBr Cs+, Br- cesium bromide
MgO Mg2+, O2- magnesium oxide
p.99 Table 4.2 Common Type II Cations
Ion System Name Older Name Ion System Name Older Name
Fe3+ iron (III) ferric Sn4+ tin (IV) stannic
Fe2+ iron (II) ferrous Sn2+ tin (II) stannous
Cu2+ copper (II) cupric Pb4+ lead (IV) plumbic
Cu+ copper (III) cuprous Pb2+ lead (II) plumbous
Co3+ cobalt (III) cobaltic Hg2+ mercury (II) mercuric
Co2+ cobalt (II) cobaltous Hg22+ * mercury (I) mercurous
*Mercury (I) ion always occur bond together in pairs to form Hg22+
p.104 Rules for Naming Type III Binary Compounds
1. The first element in the formula is named first, and the full element name is used.
2. The second element is named as though it were an anion.
3. Prefixes are used to denote the numbers of atoms present. These prefixes are given in Table 4.3
Table 4.3 (p.104) Prefixes Used to Indicate Numbers in Chemical Names
Prefix Number Indicated
mono- 1
di- 2
tri- 3
tetra- 4
penta- 5
hexa- 6
hepta- 7
octa- 8
nona- 9
deca- 10
p.106 Let’s Review
Type I: Ionic compounds with metal that always form a cation with the same charge.
Type II: Ionic compounds with metals (usually transition metals) that form cations with various charges.
Type III: Compounds that contain only nonmetals.
Naming and Writing Formulas for More Complex Compounds (p.109 – p.116)
(P.109) Table 4.4 Names of Common Polyatomic Ions
Ion Name Ion Name______
NH4+ ammonium CO32- carbonate
NO2- nitrite HCO3- hydrogen carbonate
NO3- nitrate (bicarbonate is widely used common name)
SO32- sulfite ClO- hypochlorite
SO42- sulfate ClO2- chlorite
HSO4- hydrogen sulfate (bisulfate is ClO3- chlorate
a widely used common name) ClO4- perchlorate
OH- hydroxide C2H3O2- acetate
CN- cyanide MnO4- permanganate
PO43- phosphate Cr2O72- dichromate
HPO42- hydrogen phosphate CrO42- chromate
H2PO4- dihydrogen phosphate O22- peroxide
Naming Acids (p.113- p.115)
Rules for Naming Acids (p.113)
1. If the anion does not contain oxygen, the acid is named with the prefix hydro- and suffix –ic attached to the root name for the element. For example, when gaseous HCl, HCN, and H2S are dissolved in water, they form the following acids:
Acid Anion Name______
HCl Cl- hydrochloric acid
HCN CN- hydrocyanic acid
H2S S2- hydrosulfuric acid
2. When the anion contains oxygen, the acid name is formed from the root name of the central element of the anion or the anion name, with a suffix of –ic or –ous. When the anion name ends in –ate, the suffix –ic is used,
Acid Anion _____Name______
H2SO4 SO42- (sulfate) sulfuric acid
H3PO4 PO43- (phosphate) phosphoric acid
HC2H3O2 C2H3O2- (acetate) acetic acid
When the anion name ends in –ite, the suffix –ous is used in the acid name. For example,
Acid Anion Name______
H2SO3 SO32- (sulfite) sulfurous acid
HNO2 NO2- (nitrite) nitrous acid
p.114 Table 4.5
Names of Acid that Do Not Contain Oxygen
Acid Name______
HF hydrofluoric acid
HCl hydrochloric acid
HBr hydrobromic acid
HI hydroiodic acid
HCN hydrocyanic acid
H2S hydrosulfuric acid
p.114 Table 4.6
Name of Some Oxygen-Containing Acids
Acid Name______
HNO3 nitric acid
HNO2 nitrous acid
H2SO4 sulfuric acid
H2SO3 sulfurous acid
H3PO4 phosphorous acid
HC2H3O2 acetic acid
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