Chem-To-Go Lesson 14Unit 4

IONIC BONDING -

NAMING

Need a periodic table and an ion sheet

1. Write the name of the metal element, which is the positive ion.

2. If the metal is a transition metal (except for Ag or Zn), draw parentheses for the Roman numeral. We’ll fill it in later.

3. Write the name of the negative ion.• If it is a monatomic ion (a plain ol’

element), then the ending will be –ide.

• If it is a polyatomic ion, then the ending will be probably be –ite or –ate.

4. Fill in the Roman numeral. You’ll need to determine the ORIGINAL charge of cation. It’s that positive charge that goes in the parentheses.

HOW TO NAME IONIC COMPOUNDS

Al2(SO4)3

1. Write the name of the metal element, which is the positive ion.

2. If the metal is a transition metal (except for Ag or Zn), draw parentheses for the Roman numeral. We’ll fill it in later.

3. Write the name of the negative ion.• If it is a monatomic ion (a plain ol’

element), then the ending will be –ide.

• If it is a polyatomic ion, then the ending will be probably be –ite or –ate.

4. Fill in the Roman numeral. You’ll need to determine the ORIGINAL charge of cation. It’s that positive charge that goes in the parentheses.

EXAMPLE 2CaCl2

Tip: Be careful not to mistake the Cl2 portion for ClO2. Most polyatomic ions can be

recognized by looking for O.

1. Write the name of the metal element, which is the positive ion.

2. If the metal is a transition metal (except for Ag or Zn), draw parentheses for the Roman numeral. We’ll fill it in later.

3. Write the name of the negative ion.• If it is a monatomic ion (a plain ol’

element), then the ending will be –ide.

• If it is a polyatomic ion, then the ending will be probably be –ite or –ate.

4. Fill in the Roman numeral. You’ll need to determine the ORIGINAL charge of cation. It’s that positive charge that goes in the parentheses.

EXAMPLE 3Na2CO3

Helpful Tip: Don’t be intimidated by polyatomic ions. Simply find the metal, and the rest of the compound is the anion. If the

anion has more than one element, then it is a polyatomic

ion.

1. Write the name of the metal element, which is the positive ion.

2. If the metal is a transition metal (except for Ag or Zn), draw parentheses for the Roman numeral. We’ll fill it in later.

3. Write the name of the negative ion.• If it is a monatomic ion (a plain ol’

element), then the ending will be –ide.

• If it is a polyatomic ion, then the ending will be probably be –ite or –ate.

4. Fill in the Roman numeral. You’ll need to determine the ORIGINAL charge of cation. It’s that positive charge that goes in the parentheses.

EXAMPLE 4CuF2

Helpful Tip: Don’t ever backwards criss-cross to find the polyatomic ion. If the subscripts have been reduced, then you’ll

make a mistake.

LiNO2 LiNO3

COMPARISON EXAMPLES

Li3N