Naming Binary Molecular Compounds

Up until now, we’ve always named bonds that included a metal cation bonding to either a non metal anion or a polyatomic ion. Bu what if we bond two non metals together? This is no longer an Ionic bond, this is a covalent bond. We call this group Molecular compounds!

Nonmetal + Nonmetal = Molecular Compound

When naming molecular compounds, we use prefixes to identify how many of each type of element are present in the compound.

  1. Mono *                 6. Hexa
  2. Di                            7. Hepta
  3. Tri                           8. Octa
  4. Tetra                      9. Nona
  5. Penta                    10. Deca

*The only time we vary from this is when there is only one of the first type of element we don’t add mono. For example, CO is Carbon monoxide, not Monocarbon monoxide.

The final rule for naming Molecular compounds is that the second element, when it is a nonmetal, the ending is changed to the suffix “-ide”. For example, Sulfur would be sulfide.

So for example, P4O10 would be Tetraphosphorus Decaoxide

Now you try! The problems and answer keys are available on the Chemistry: Semester 1 Page under Unit 4: Naming

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s