Lesson 5: Writing the Formulas and Names of Ionic Compounds

Writing the Formulas and Names of Ionic Compounds 

Objectives: 
Write the name of an ionic compound when given the chemical formula of the compound.
Write the chemical formula of an ionic compound when given the name of the compound.

PART 1: Writing Ionic Formulas Practice
Rules for finding the formula for Ionic Compound:
Determine the charge of the metal when it forms an ion.
Determine the charge of the nonmetal when it forms an ion.
Combine the two ions to form an neutral compound. Determine the number of atoms of each element needed to balance positive and negative charges. 

WATCH THIS! Watch the video below to understand the basics of writing chemical formulas for ionic compounds. 

DIRECTIONS! For questions 1-7, determine the formula for each of the ionic compounds below. 
You will not be able to type subscripts so your formulas may look like this P4O6.
Do not use Google! This is a skill that you HAVE to know how to do in order to be successful in AP Chemistry. 

1

lithium bromide

1

magnesium oxide

1

calcium nitride

1

aluminum fluoride

1

cesium sulfide

1

strontrium phosphide

1

strontium chloride

The metals in the middle section of the periodic table are called transition metals. These metals can lose various amounts of electrons and therefore can form multiple charges. 

Watch the video below to know how to write the formulas of ionic compounds that contain transition metals. 

DIRECTIONS! For questions 8-13, determine the formula for each of the ionic compounds below.
You will not be able to type subscripts so your formulas may look like this P4O6.
Do not use Google! This is a skill that you HAVE to know how to do in order to be successful in AP Chemistry.

1

What does the roman numeral in the name chromium (III) phosphide represent?

* Remember, prefixes are only used when the compound is covalent. 

1

mercury (II) oxide

1

copper (I) chloride

1

nickel (I) oxide

1

lead (IV) sulfide

1

manganese (VIII) oxide

Polyatomic ions are created when a group of atoms that covalently bond together to form a compound. In order for those group of atoms to successfully bond together, electrons either had to be lost or gain which results in a charge forming. Since these compounds have a charge, they form ionic bonds. The list of polyatomic ions below are the ones that will most often be used in class. 

Watch the video below to learn how to write chemical formulas for ionic compounds that contain polyatomic ions.

DIRECTIONS! For questions 14-18, determine the formula for each of the ionic compounds below.
You will not be able to type subscripts so your formulas may look like this P4O6.
Do not use Google! This is a skill that you HAVE to know how to do in order to be successful in AP Chemistry.

1

copper (I) hydroxide

1

aluminum nitrate

1

iron (II) phosphate

1

cobalt (II) phosphite

1

ammonium sulfate

1

Match the correct ionic compound name to the correct formula. You will also be asked to identify the which formulas are incorrect formula as well.

Draggable item		Corresponding Item

Part 2: Naming Ionic Compounds Practice
Rules for naming ionic compounds: 

1) Write the name of the cation (+ charged ion). 
IF the cation is a transition metal (a metal located in the d block) you must include a roman numeral the name to indicated the charge of the metal. 
2) Write the name of the anion. 
IF the anion is a nonmetal changed the ending of the name to -ide. For example, chlorine becomes chloride. 
IF the anion is a polyatomic ion, write the name of the polyatomic as is. Do not change the ending of its name.
Watch the video below to see examples of how to name ionic compounds. 


Directions! For questions 20-30, determine the name of each of the ionic compounds below. 
Do not use Google! This is a skill that you HAVE to know how to do in order to be successful in AP Chemistry.

1

K2S

1

CuBr2

1

CoN

1

AlP

1

NaNO3

1

BaCl2

1

CaCO3

1

CuSO4

1

Fe2O3

1

Be3N2

1

Draggable item		Corresponding Item

Draggable item		Corresponding Item
incorrect formula for beryillium nitride		Cu2O
beryillium nitride		CuO
incorrect formula for magnesium carbonate		Be3N2
magnesium carbonate		Be2N3
incorrect formula for copper (II) oxide		MgCO3
copper (II) oxide		MgC

Draggable item		Corresponding Item
Zn(NO3)2		lead (IV) chloride
Incorrect name for Cs2O		lead chloride
Incorrect name for NaClO		sodium hypochlorite
Incorrect name for Zn(NO3)2		sodium chloride oxide
PbCl4		cesium oxide
NaClO		cesium (I) oxide
Incorrect name for Zn(NO3)2		zinc (II) nitrate
Cs2O		zinc nitrate
incorrect name for PbCl4		zinc nitrogen oxide

Lesson 5: Writing the Formulas and Names of Ionic Compounds

Writing the Formulas and Names of Ionic Compounds

PART 1: Writing Ionic Formulas Practice

lithium bromide

magnesium oxide

calcium nitride

aluminum fluoride

cesium sulfide

strontrium phosphide

strontium chloride

What does the roman numeral in the name chromium (III) phosphide represent?

mercury (II) oxide

copper (I) chloride

nickel (I) oxide

lead (IV) sulfide

manganese (VIII) oxide

copper (I) hydroxide

aluminum nitrate

iron (II) phosphate

cobalt (II) phosphite

ammonium sulfate

Match the correct ionic compound name to the correct formula. You will also be asked to identify the which formulas are incorrect formula as well.

Part 2: Naming Ionic Compounds Practice

K2S

CuBr2

CoN

AlP

NaNO3

BaCl2

CaCO3

CuSO4

Fe2O3

Be3N2

Writing the Formulas and Names of Ionic Compounds

PART 1: Writing Ionic Formulas Practice

lithium bromide

magnesium oxide

calcium nitride

aluminum fluoride

cesium sulfide

strontrium phosphide

strontium chloride

What does the roman numeral in the name chromium (III) phosphide represent?

mercury (II) oxide

copper (I) chloride

nickel (I) oxide

lead (IV) sulfide

manganese (VIII) oxide

copper (I) hydroxide

aluminum nitrate

iron (II) phosphate

cobalt (II) phosphite

ammonium sulfate

Match the correct ionic compound name to the correct formula. You will also be asked to identify the which formulas are incorrect formula as well.

Part 2: Naming Ionic Compounds Practice

K2S

CuBr2

CoN

AlP

NaNO3

BaCl2

CaCO3

CuSO4

Fe2O3

Be3N2

Match the ionic formula to the correct name. Not all of the names will have a matching formula so choose wisely!