Naming Ionic Compounds with Polyatomic Ions

Naming Ionic Compounds - Type I, II, and III

by Jessica Holmes

Type I binary ionic compounds review

Type I Ionic compounds

• Comprised of a metal ion and a nonmetal ion

• The metal anion is a cation (a positively charged ion)

• The nonmetal is an anion (a negatively charged ion)

• In Type I ionic compounds, the cations only come in one "flavor" of charge. Example: sodium is always +1

To name Type I binary ionic compounds:

• Put the cation (metal) first. Use the entire name of the metal. Example: sodium, potassium, calcium, etc.

• Put the name of the anion (nonmetal) section. Change the ending to "-ide." Example: oxide, bromide, chloride, nitride, etc.

• Ions always combine in a way that the charges balance each other. E.g., if you have one calcium (2+ charge), you need 2 chlorines (1- charge) to balance it out.

• Even if a type 1 ionic compound has two copies of an ion (e.g. CaCl₂), it will always be named using the same procedure(e.g., calcium chloride).

Multiple Choice

Which of the following is NOT an ionic compound:

• CaO
• NaOH
• BaCl₂
• Br₂

Multiple Choice

What is the correct chemical formula for magnesium chloride?

• MgCl

• Mg₂Cl

• MgCl₂

• MgCl₃

• Mg₃Cl

Multiple Choice

How do the following two elements bond together?
Na¹⁺  F^1-         

• NaF
• NaF₃
• Na₃F
• Na₁F₂

Multiple Choice

How do the following two elements bond together?
Cr³⁺  O^2-         

• CrO
• Cr₃O₂
• Cr₂O₃
• CrO₃

Multiple Choice

KCl

• Krypton Chloride
• Potassium Chlorine
• Potassium Chloride
• Potassium Monochloride

Multiple Choice

LiBr is called

• lithium bromine
• lithium (I) bromine
• lithium bromide
• lithuim (I) bromide

Multiple Choice

What is the correct formula for Sodium Oxide?

• NaO
• NaO₂
• Na₂O
• Na₂O₂

​We can use the ions to write the chemical formula of a type (II) compound)

​iron (III) fluoride is the bond between Fe+3 and F-1 meaning that the compound formed is:

​

​FeF3

Polyatomic Ions

There are also ions that form after elements have shared electrons. These ions are known as polyatomic ions, and each polyatomic ion already has a name.

Multiple Choice

What is the name of this polyatomic ion: CO₃^2- ?

• carbide

• carbonate

• carbonite

• chlorate

Multiple Choice

What is the name of this polyatomic ion: NO₂^1- ?

• nitride

• nitrate

• nitrite

Naming with Polyatomic Ions

• When polyatomic ions are used, simply use the name of the polyatomic ion in the compound.

• Example:

• CaSO₄

• Calcium Sulfate

Polyatomic Formulas

This is just as easy to do with polyatomic ions. You just need to use the name of the polyatomic ion.

Step 1: Write the symbol of the metal ion.

Step 2: Write the formula of the polyatomic ion.

Step 3: Determine the charges using the periodic table and the table of polyatomic ions.

Step 4: Determine the formula from the ions.

Multiple Choice

What is the correct formula for the compound: ammonium hydroxide?

• NH₄(OH)₄

• NH₅O

• NH₄OH

Multiple Choice

What is the correct formula for the compound: Lead (II) Nitrate?

• PbNO₃

• Pb(NO₃)₄

• Pb₃NO₂

• Pb(NO₃)₂

Now let's practice!

Multiple Choice

AgF

• silver fluoride
• silver fluorine
• monosilver monofluoride
• silver monofluorine

Multiple Choice

The proper formula for magnesium hydroxide:

• MgOH
• Mg₂OH
• Mg(OH)₂
• Mg₂OH₂

Multiple Choice

Name the following ionic compound: LiNO₃

• lithium nitrate
• lithium III nitrate
• lithium nitride
• lithium oxide

Multiple Choice

Name the following ionic compound: MgSO₄

• magnesium sulfoxide
• magnesium sulfide
• magnesium sulfate
• magnesium oxide

Multiple Choice

Name the following ionic compound: BeCl₂

• beryllium chlorine
• beryllium II chloride
• beryllium chloride
• beryllium dichloride

Multiple Choice

The chemical formula of lead (IV) nitrate is

• PbN₄
• PbNO₃₄
• Pb(NO₃)₄
• Pb₃NO₄

Multiple Choice

The chemical formula of iron (III)bromide is

• FeBr
• Fe(III)Br
• FeBr₃
• Fe₂Br₃

Multiple Choice

The chemical formula of iron (III)bromide is

• FeBr
• Fe(III)Br
• FeBr₃
• Fe₂Br₃

Multiple Choice

What is the formula for calcium phosphide?

• CaP
• Ca₂P₃
• Ca₃P₂
• Ca₂P

Multiple Choice

What is the formula for copper(I) sulfate?

• CuSO₃
• CuSO₄
• Cu₂SO₃
• Cu₂SO₄

Multiple Choice

The chemical formula for an ionic compound of potassium and oxygen is

• KO.
• K₂O.
• K₂O₂.
• KO₂.

Multiple Choice

The name of FeCl₂ is

• iron chloride

• iron (II) chloride

• iron (I) chloride

• iron dichloride

Multiple Choice

LiBr is called

• lithium bromine

• lithium (I) bromine

• lithium bromide

• lithuim (I) bromide

Multiple Choice

What is the name of the compound Na₂(SO₄)?

• Sodium sulfate

• Sodium sulfide

• Sodium sulfite

• Sodium sulfuroxide

Multiple Choice

What is the correct formula for Sodium Oxide?

• NaO
• NaO₂
• Na₂O
• Na₂O₂

Multiple Choice

What is the correct molecular formula for barium hydroxide?

• Ba(OH)₂

• Ba₂OH

• BaOH

• Ba₂OH

Multiple Choice

What is the formula for copper(I) sulfate?

• CuSO₃
• CuSO₄
• Cu₂SO₃
• Cu₂SO₄

​Great job! You did it!