Nomenclature Part 1Naming Binary Compounds

Naming Compounds…Why?

How many compounds are currently known?

With 4 million known compounds, is it convenient to have to memorize their names?

We have rules for naming compounds so that they can all be named generically.• By naming them all at once, we don’t have to

memorize the names of any!

Naming Binary Compounds Binary Compounds are

compounds composed of only two elements…

There are 4 types of Binary Compounds:

1. Binary Ionic Compounds (Type I)2. Binary Ionic Compounds (Type II)3. Binary Covalent Compounds4. Acids (to be discussed later)

What is a Binary Ionic Compound?

Binary Ionic Compounds are made of a cation and an anion joined together in an ionic bond.• They are held together by magnetic attraction.• When a metal combines with a nonmetal,

the resultant compound is always a binary ionic compound.

The cation can be a main group metal, a transition metal, or a polyatomic ion.

The anion can be a main group nonmetal, or a polyatomic ion.• There are two types, which are distinguished by the type of cation.

Type I Binary Ionic Compounds

Type I Binary Ionic Compounds are made of a metal that forms only one cation, and an anion.

The cation is named first.• Metal cations are named using their atomic

names. In general, groups 1, 2, and 3 form only one cation.

The anion is named second.• Remember to drop the ending of the anion’s

atomic name and add the suffix –ide.

Practice: Name the following Type I Binary Ionic Compounds

NaCl BaO CaS KI CsBr SrCl2 Li2Se Mg3P2

Sodium ChlorideBarium OxideCalcium SulfidePotassium IodideCesium BromideStrontium ChlorideLithium SelenideMagnesium Phosphide

Type II Binary Ionic Compounds Type II binary ionic compounds are made up of a

metal that forms more than one cation (transition and rare earth), and an anion.

The cation is named first.• Metal cations are named using their atomic names.

The charge of the cation is indicated in roman numerals in parenthesis.• This is necessary because these metals form more than one

cation, and we need to know which one it is.

The anion is named last.• Remember to drop the ending of the anion’s atomic

name and add the suffix –ide.

Practice: Name the following Type II Binary Ionic Compounds

FeCl2 CuBr HgO Fe2O3

MnO2

PbCl4 FeBr3

Co3P2

Iron (II) ChlorideCopper (I) BromideMercury (II) OxideIron (III) OxideManganese (IV) OxideLead (IV) ChlorideIron (III) BromideCobalt (II) Phosphide

Binary Covalent Compounds

Type III

Get through Part I notesExit quiz today on BCCHW: Pg 132 # 21, 22, 23, 34 due Tues

What is a Binary Covalent Compound?

Binary Covalent Compounds are made up of two different nonmetals.

There are no ions present in the compound.

Atoms are bonded covalently, by sharing electrons.

Binary Covalent Compounds are named using a system of numeric prefixes.

The Numeric Prefixes 1 – mono-

2 – di-

3 – tri-

4 – tetra-

5 – penta-

6 – hexa-

7 – hepta-

8 – octa-

9 – nona-

10 – deca-

Naming Binary Covalent Compounds

The first element is named first.• The elements atomic name is used.

The second element is named second.• This element is named as if it were an anion.• Remember to drop the ending of the anion’s atomic name and

add the suffix –ide.

The number of each atom present in the compound is represented by a numeric prefix. (mono, di, tri, …)

The prefix mono is NOT used in naming the first element in the compound.

Practice: Name the following Binary Covalent Compounds

BF3

NO NO2

N2O N2O5

CCl4 SO2

IF5

Boron TrifluorideNitrogen MonoxideNitrogen DioxideDinitrogen MonoxideDinitrogen PentoxideCarbon TetrachlorideSulfur DioxideIodine Pentafluoride

Naming Binary Compounds: Summary

Binary Compound

?

Yes

Metal Present?

No

Yes

BCC – Use Prefixes

Does the metal form more than one cation?

No

Yes

BIC – Type II, Use Roman Numerals

BIC – Type I, No Roman

Numerals

Practice: Name the following Binary Compounds

CuO SrO B2O3

TiCl4 K2S OF2

NH3

Copper (II) OxideStrontium OxideDiboron TrioxideTitanium (IV) ChloridePotassium SulfideOxygen DifluorideNitrogen Trihydride

Ammonia

Practice: Name the following Binary Compounds

ClF3

VF5

CuCl MnO2

MgO H2O

Chlorine TrifluorideVanadium (V) FluorideCupper (I) ChlorideManganese (IV) OxideMagnesium MonoxideDihydrogen Monoxide

Water