Ionic Compounds (p. 176 – 180, 203 – 211)

Ionic Compounds Most of the rocks and minerals that make up

Earth’s crust consist of positive and negative ions held together by ionic bonding.

An ionic compound is composed of positive and negative ions that are

combined so that the numbers of positive and negative charges are equal.

Most ionic compounds exist as crystalline solids

Ionic Compounds The chemical formula of an ionic

compound merely represents the simplest ratio of the compound’s combined ions that gives electrical neutrality.

A formula unit is the simplest collection of atoms from which an ionic

compound’s formula can be established.

Crystal structure of NaCl

Ratio is 6:6 or 1:1

Crystal structure of CaF2

Dot Diagrams

show transfer of e-

Dot Diagramsshow transfer of e-

Electron Dots For Cations

Ca

Electron Dots For Cations

Ca

Electron Dots For Cations

Ca+2

Electron Dots For Anions

P P-3

Ionic Bonding

Ca+2 P -3

Ca+2P

-3

Ca+2

Ionic Bonding

Ca3P2

Calcium phosphide

Common Ion Charges

1+

2+ 3+NA 3- 2- 1-

0

Ionic Nomenclature

varies

Binary Ionic compoundsMade of two different elements

that have formed ionsEnd in -ide

Monatomic ions – p. 205 Ions formed from a single atom Metals from positive monatomic

ions Nonmetals form negative

monatomic ions ( nonmetal ions end in –ide, ex. Chlorine becomes the chloride ion)

Variable oxidation #’s Some elements have more than

one oxidation number. Groups 3 - 12, tin, lead. The stock

system of nomenclature uses roman numerals to indicate the oxidation number.

(p.205)

Al 3+ O 2-

 Al 2 O 3

 (6 +) + (6-) = 0

Formula is Al2O3

Write the formulas for these Lithium sulfide tin (II) oxide tin (IV) oxide Magnesium fluoride Silver chloride Iron (III) phosphide Iron (III) sulfide Potassium iodide

Write the formulas for these Sodium sulfide Aluminum sulfide Aluminum nitride Copper (II) bromide Iron (II) oxide Lead (II) chloride Mercury (II) sulfide

Compounds with polyatomic ions

Review the list on page 210 All are negative except the ammonium

ion Most are oxyanions (contain oxygen) When more than one polyatomic ion is

in a compound, parentheses must be placed around the polyatomic ion.

Compounds with polyatomic ions Copper (II) sulfate calcium nitrate barium nitrate Ammonium chloride ammonium sulfide Lithium nitrate Sodium carbonate Potassium perchlorate

Naming Binary Ionic Compounds

Write the name of the cation firstWrite the root of the anion, end

in -ideNaCl = sodium chlorideMgBr2 = magnesium bromideKI = potassium iodideBaO = barium oxide

Naming Binary Ionic Compounds

The problem comes with the variable transition metals.

You must determine the roman numeral.

CuOCoCl3 Cu2SFe2O3

SnCl2CrNSc3P2

PbOPbO2

Ionic Compounds with polyatomic ionsthe ending of the polyatomic ion doesn’t change

NaNO3

CaSO4

CuSO3

(NH4)2O

LiCN

Fe(OH)3

(NH4)2CO3

NiPO4

FeCrO4

Pb3(PO4)2

See Sample Problems 7-1,7-2,7-3(p.207,209,211) h.w. p. 236 # 27, 41,Handout p.2