Ionic, covalent, polyatomic...are those even real words?

Listening to a science class can really sound like a foreign language sometimes. It's like people tried to come up with the most confusing words they could think of. And then they used other complicated words to describe the first set of complicated words (like stoichiometry? even the spell-check thinks the word is made up).

And then they want you to name the compounds. And if you try to give them nice names like Buttercup or Hugo they don't give you any credit at all... They want you to follow a very confusing set of rules just to give the simple looking symbols long confusing names. Nitrogen triiodide (which by the way is so explosive it will ignite it touched by a feather) has a name that looks like it can't possibly be real, or at least must be spelled wrong. Who puts two "i"s in a row in a word anyways.

The rules don't really have to be that complicated if you break it down in to pieces. First you have to figure out if the compound you have is ionic or covalent (there are also acids, organic compounds and other special compounds, but that is for a different post).

Remember that an ionic compound is made of one positive and one negative ion. That almost always means one metal and one nonmetal. The only common exceptions are hydrogen, which can act like either a nonmetal or a metal depending on the situation, and the polyatomic ions which are a dead giveaway that you have an ionic compound. Hydrogen you can name like a metal in simple compounds.The polyatomic ions each have a special name, like sulfate or hydroxide, and they keep that name in the compound.

Ionic compounds are named by giving the name for metal followed by the name of the nonmetal.

• Ending of the nonmetal is changed to -ide (oxygen becomes oxide, chlorine becomes chloride)
• Polyatomic ions keep their -ite and -ate endings
• If the metal can have more than one charge[transition metals plus tin and lead, minus silver, cadmium and zinc], include the Roman Numeral for the charge it has in that compound
  

Covalent compounds are made of only nonmetals. Since they can go together in more than one combination (N2O, NO2, N2O3) you can't just use the element names, no one would know which nitrogen oxide you had. So we use prefixes, or extra letters in front of the name, to show how many of that element are in the particular element you are trying to name right now.

So N2O would be dinitrogen monoxide, di- meaning 2 for the two nitrogens, and mono- meaning 1 for the one oxygen. NO2 would be nitrogen dioxide, notice that it isn't mononitrogen. One of the goofy things with the prefixes is that is if the first element is only one, they don't include the mono-, but if the second element is one they do.