Ch. 15 and 6 Naming and Writing Formulas for Ionic Compounds

Writing Formulas for Binary Ionic Compounds

Ch. 6

A. Formula Unit: the lowest whole-number ratio of ions in an ionic compound

Writing Formulas for Binary Ionic Compounds

B. Rules:1. Write symbol and charge for both cation and

anion.2. Crisscross the numbers for the charges and

write as subscripts.3. CHECK!! The formula must be in the lowest

possible ratio of ions (this means reduce).

The cation is always written first!

practice problemsWrite formulas for these compounds:

A. calcium iodide

Ca I+2

-

CaI2

21

B. Aluminum sulfide

Al S

Al2S3

+3

-232

O -2

C. Tin (IV) oxide

Sn+4

Sn2O4 SnO2

42

Be O

BeO

+2

-2D. Beryllium Oxide

2 2

Be2O2

Naming Binary Ionic Compounds1.) Name the cation.

Use Roman Numerals if Transition Metal.

2.) Name the anion.Drop their last names ending, put –ide in its place

NaCl Sodium IonChlorine Ion

Sodium Chloride

(Middle Name, a roman numeral)

Naming Binary Ionic Compounds that contain a transition metal

• Use Roman numerals (middle name) to show the charge of the ion. Many of these elements can form more than one ion:Cr2+ Chromium II or Cr3+ Chromium IIICu+ Copper I or Cu2+ Copper IIMn2+ Manganese II or Mn3+ Manganese III Fe2+ Iron II or Fe3+ Iron IIICo2+ Cobalt II or Co3+ Cobalt IIISn2+ Tin II or Sn4+ Tin IVPb2+ Lead II or Pb4+ Lead IVZn1+ Zinc I or Zn2+ Zinc IINi2+ Nickel II or Ni3+ Nickel III

SnS2

Naming Binary Ionic Compounds

Use Middle Name

Tin(IV)

Find SnWhere is it located?-

2

Sulfide

B.) CuBr2

practice problemsA.) KCl Potassium chloride

Copper (II) bromide

C.) AlF3 Aluminum fluoride

D.) MgO Magnesium oxide

E.) MnI2 Manganese (II) iodide

F.) ZnS zinc (II) sulfide

Practice Problems

1.) Na+ Cl- Na

Cl

Show Understanding by SHOWING YOUR WORK

Sodium chloride

2.) K+ S-2 K2S

Potassium sulfide

3.) Al+3 I- AlI3

Aluminum iodide

4.) Ag+ O-2 Ag2O

Silver (I) oxide

5.) Ni+2 O-2Ni2O2 Ni

ONickel (II) oxide

6.) Pb+4 O-2Pb2O4 PbO2

Lead (IV) oxide

Ionic Review

Write formulas for these binary ionic compoundsa. Barium Sulfideb. Tin (IV) Chloridec. Magnesium Nitrided. Sodium Oxide

BaSSnCl4

Mg3N2

Na2O

Review (cont.)

Name these binary ionic compounds:a. KClb. BaOc. CuBr2

d. FeS

Potassium chlorideBarium oxideCopper (II) bromideIron (II) sulfide