Naming Ionic and Covalent Compounds

Ionic Compounds
- made of  negatively and  positively charged particles(metal and a non-metal)
- to try and make themselves stable, atoms transfer electrons and become ions
- take the valence shell configuration of the nearest noble gas
- make ionic lattices in solids

To write ionic compounds, you need a metal and a non-metal.  For example, let's work with Lithium Fluoride. The first element in a name is always the metal ion.  Find the two components and their charges.  In this case its Lithium+ and Fluorine-.  Switch the charges on the atoms and write the compound out.  The balanced charges should be written on the lower right corner of the symbol.  LiF(in this case since the charges are both 1, you don't need to write them)

Let's work through a few more:

Magnesium Chloride = Mg+2 and Cl-1 -> Mg1 and Cl2 -> MgCl2

Sodium Sulphide = Na+ and S-2 -> Na2 and Cl1 -> Na2Cl

Beryllium oxide = Be+2 and O-2 -> Be2 and O2(cancel each other out!) -> BeO

When working with polyatomic ions, refer to the chart.  Put the whole ion in brackets if charges cross.

Potassium Chlorate = K+ and ClO3- -> KClO3

Chromium (II) Nitrate = Cr+2 and NO3- ->Cr(NO3)2

Common Polyatomic Ions

 To write its name, basically reverse the steps you did to write its symbol.  However, before you start, there are several things you should know.  Unless you're naming compounds with polyatomic ions, change the ending of the anion to "ide".  To write multivalent metals you must include the charge in brackets in roman numerals. 

Let's work through several examples:
ZnF2 = Zn+2 and F- ->Zinc Fluoride
AuCl3 = Au+3 and Cl- ->Gold (III) Chloride
Fe2(SO3)3 = Fe+3 and SO3-2 -> Iron(III) Sulphite

If you want to get some practise, here's a great site:
http://www.teacherbridge.org/public/bhs/teachers/Dana/ionic.html

Covalent Compounds
- two non-metals
- share electrons and become a molecule
- valence shells take the formation of the nearest noble gas
-diatomic molecules exist in our environment: H2, N2, O2, F2, Cl2, I2, and Br2.

Naming covalent compounds is much easier than ionic compounds.  Similar to ionic compounds, cross the charges.  All you have to do is add a prefix depending on the amount of particles there are.

Let's work through some examples:
Carbon dioxide = C and since the prefix is "di", there are 2 oxides. -> CO2
Carbon tetrafluoride = CF4
N2 = nitrogen gas

SF6 = Sulphur hexafluoride (only add "mono" if it's only one on the second element)
Si2Se4 =disilicon tetreselenide
Cl2Se = Dichloride monoselenide