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