Chemistry 0010

Naming Compounds

Topics you should learn:
1. Binary compounds:
   • containing two nonmetals
   • containing metals with fixed ionic charges
   • containing metals with variable ionic charges
2. Ternary compounds

3. Hydrates

4. Binary Acids

5. Oxy Acids

1. how to write chemical formulas from their names AND
2. how to write the names from their chemical formulas.

1. containing two nonmetals

   Examples:

   Rules:

   1. The second element has the ending -ide.
   2. The number of atoms of each element is indicated with Greek prefixes. In the case of mono-, it is only used for the second nonmetal. When no prefix appears, one atom is assumed.
   3. If two vowels appear next to each other, the vowel from the Greek prefix is dropped. This is for ease of pronunciation.
      • monooxide becomes monoxide

      • tetraoxide becomes tetroxide

      • pentaoxide becomes pentoxide

   [RETURN TO TOP OF PAGE]

   ---

2. containing metals with fixed ionic charges

   Some metals have fixed charges. Click to make sure you know which ones they are. There are thirteen of them to learn.

   Examples:

   Rules:

   1. Name the metal first followed by the nonmetal with the ending -ide.
   2. No Greek prefixes necessary here because the metal has a fixed charge and, therefore, in forming a compound, there is only one possible combination with the nonmetal.

   [RETURN TO TOP OF PAGE]

   ---

3. containing metals with variable ionic charges

   Here you have to consider the charge associated with the metal cations. You need to become familiar with the latin names of five common metal ions because they are still in use in today's literature.

   Examples:

   Rules:

   1. Name the metal followed by a Roman numeral in parentheses immediately following the name of the metal. The Roman numeral represents the charge of the metal.
   2. Name the nonmetal with the ending -ide.
   3. No Greek prefixes necessary here because the charge on the metal is labelled, therefore, in forming a compound, there is only one possible combination with the nonmetal.

   [RETURN TO TOP OF PAGE]

Read: 7-1 - Systematic Chemical Names (page 166) 7-2 - Binary Compounds Containing Two Nonmetals (page 166) 7-3 - Binary Compounds Containing a Metal and a Nonmetal (page 168)

[RETURN TO TOP OF PAGE]

Send Comments to Rosamaría Fong.

Ternary Compounds

For this course, you need to learn some polyatomic ions. Click here for the ones that you need to learn. Be sure to learn their names, formulae and their charges.

Examples:

Rules:

1. Decide if the metal is a metal with fixed ionic charge or variable charge.
2. Name the polyatomic anion following the name of the metal.
3. No Greek prefixes necessary here because the metal charge is either implicitly or explicitly specified and, therefore, in forming a compound, there is only one possible combination with the polyatomic anion.
4. For compounds containing NH₄⁺ cations:
   • Name the cation first followed by the anion (remember that for simple anion, the ending is in -ide ).

[RETURN TO TOP OF PAGE]

Read: 7.4 - Ternary and Higher Compounds (page 171)

Back to course content page

Send Comments to Rosamaría Fong.

Hydrates

A crystalline compound that contains chemically bound water molecules in definite proportions is called a hydrate.

Examples:

Rules:

1. Name the anhydrous salt . Again, determine whether the metal in the anhydrous salt is one that is fixed ionic charge or variable charge.
2. Name the chemically bound water molecules with the word 'hydrate' with the appropriate Greek prefix to indicate the number of water molecules in the formula unit.

[RETURN TO TOP OF PAGE]

Read: 13.7 - Hydrates (page 347)

[RETURN TO TOP OF PAGE]

Back to course content page

Send Comments to Rosamaría Fong.

Binary Acids

Binary acids are hydrogen-containing compounds. As the pure compound (ie- in the gaseous or liquid state), they have different properties than they do in aqueous solution of the compound.

Acids are hydrogen-containing compounds that yield hydrogen ions (H⁺) in water.

Examples:

Rules:

1. As the pure compound (ie - in the gaseous or liquid state),
   • start with 'hydrogen'
   • follow by the anion name ending in '-ide'.
2. As aqueous acid solutions,
   • start with 'hydro-'.
   • change the anion name to end with '-ic'.
   • add the word 'acid' at the end.

[RETURN TO TOP OF PAGE]

Read: 7.6 - Acids, Bases, and Salts (page 174)

Send Comments to Rosamaría Fong.

Oxy Acids

These are acids which contain oxygen in the chemical formula. You need to learn some common ones. Click to see the 5 that you have to learn.

[RETURN TO TOP OF PAGE]

Read: 7.6 - Acids, Bases, and Salts (page 174)

Send Comments to Rosamaría Fong.

Rosamaría Fong, Instructor of Chemistry,
British Columbia Institute of Technology, Burnaby, B.C. Canada.

Send Comments to Rosamaría Fong.

All contents copyrighted © 1996
Rosamaría Fong, Instructor of Chemistry
All Rights reserved