CHEM 125 - Naming Simple Compounds

Type I Ionic Compounds, Type II Ionic Compounds, Type III Covalent Compounds, Polyatomic Ion Compounds, Acids

How do you name Type I Ionic Compounds?

(Main Group Metals: Cation + Anion)

Cation (Metal): use element’s full name

Anion (Monatomic Nonmetal): use modified name with “-ide” suffix

How would you name Li₂O?

Li₂O —> lithium oxide

How do you name Type II Ionic Compounds?

(Transition Metals)

Follow the Type I rules (cation + anion with “-ide” suffix), but insert a Roman numeral in parentheses after the metal name to denote its oxidation state/charge

How would you name Hg₂Cl₂?

mercury(I) chloride

How do you name Type III Covalent Compounds?

(2 Nonmetals: 1st Element + 2nd Element)

1st Element: quantitative prefix (besides “mono-”) + full element name

2nd Element: quantitative prefix + element root + “-ide” suffix

How would you name CO?

carbon monoxide

How would you name H₂O?

dinitrogen monoxide

What’s the quantitative prefix for 1?

mono-

What’s the quantitative prefix for 2?

di-

What’s the quantitative prefix for 3?

tri-

What’s the quantitative prefix for 4?

tetra-

What’s the quantitative prefix for 5?

penta-

What’s the quantitative prefix for 6?

hexa-

What’s the quantitative prefix for 7?

hepta-

What’s the quantitative prefix for 8?

octa-

How do you name polyatomic ions with “fewer” oxygens?

Ends with an “-ite” suffix

How do you name polyatomic ions with “more” oxygens?

Ends with an “-ate” suffix

How do you name polyatomic ions with the “lowest oxygen count”?

Begins with a “hypo-” prefix

How do you name polyatomic ions with the “highest oxygen count”?

Begins with a “per-” prefix

How do you name acids with an oxyanion?

Change the suffix

• “-ate” —> “-ic acid”

• “-ite” —> “-ous acid”

How do you name acids with an anion that doesn’t contain oxygen?

Add “hydro-” prefix

Change suffix to “-ic acid”

How would you name HC₂H₃O₂?

Acetic Acid

How would you name HCN?

Hydrocyanic Acid