How do we name/write chemical formulas? Its easy if you follow these rules for these types of molecules.

To write Monoatomic, and Polyatomic Ions, Remember these are the ones that are made up of two different types of atoms. First, write the symbol for the POSITIVE (+) ion Secondly, write the symbol for the NEGATIVE (-) ion. Lastly, add any subscripts that may be needed so that the positive and negative oxidation numbers are equal to zero. The molecule must be neutral!

To name Monoatomic and Polyatomic Ions, The first atom is said as it appears normally. NaOH is called Sodium Hydroxide See how the first name is said as it appears? The second half of the molecule uses a suffix at the end of it. Usually an –ide Ex. Bromide Br1- We can use an –ate, or an –ite when the negative ion is Polyatomic! Ex. Sulfate, or Sulfite (Already on Sheet So Copy Name) Sulfate is SO43- Sulfite is SO32-

Let’s see if you can name these! Fe2O3 Iron Oxide Pb(C2H3O2)2 Lead Acetate CaSO4 Calcium Sulfate Al2(SO4)3 Aluminum Sulfate LiNO3 Lithium Nitrate H2O2 Hydrogen (per)Oxide

What about Covalently bonded molecules? Naming covalent compounds that are made of two types of elements have their own special naming system. These are normally called “Binary Systems.” We use Greek Prefixes to tell the reader how many atoms of each element there are in the molecule. Mono- means one Di- means two Tri- means three Tetra- means four Penta- means five Hexa- means six Hepta- means seven Octa- means eight Nona- means nine

Let’s look at some covalently bonded molecules and see how they are named! Carbon Dioxide CO Carbon Monoxide CCl4 Carbon Tetrachloride H2O Nope, its not water, it’s Dihydrogen Oxide