1. Rules of Nomenclature for Molecular Compounds 1. The first element in the formula is named first, using the entire element name, will usually be a nonmental. 2. The second element in the formula is named using the root of the element and adding the suffix -ide. 3. Prefixes are used to indicate the number of atoms of each type that are present in the molecule. Drop the final letter of the prefix if the element begins with a vowel

2. Name each of the following molecules: CCl 4 Carbon tetrachloride NF 3 nitrogen trifluoride COCarbon monoxide As 2 O 3 Diarsenic trioxide S 4 N 4 Tetrasulfur tetranitride SiF 4 Silicon tetrafluoride SO 2 Sulfur dioxide

3. Naming Acids: Binary acids - contains hydrogen and one other element. 1. Name of a binary acid uses the prefix hydro- 2. The rest of the name consists of a form of the root of the second element ending in -ic 3. Name is followed by the word acid. HClHydrochloric acid H 3 PHydrophosphic acid HFHydrofluoric acid HIHydroiodic acid H 2 SHydrosulfuric acid

4. Naming Oxyacids Oxyacids - contains hydrogen and an oxyanion (polyatomic ion) 1. Identify the oxyanion 2. If the ending is -ate change it to ic and follow with the word acid. 3. if the ending is -ite then change it to ous and follow with the word acid. H 2 SO 4 Sulfuric acid HClO 2 Chlorous acid HClO 3 Chloric acid H 3 PO 4 Phosphoric acid H 2 SO 3 Sulfurous acid HNO 3 Nitric acid

5. Writing formulas from the names: Binary molecule - use prefixes to determine the subscripts. Acids use the reverse of the naming rules: Binary acids - begin with hydro- end in ic (use oxidation #) Oxyacids Look at suffix to determine polyatomic ion, -ic to -ate or -ous to -ite Hydrobromic acid HBr Hydronitric acidH 3 N Boric acidH 3 BO 3 Ac etic AcidHC 2 H 3 O 2 Hy pochlorous acidHClO Carbonic acidH 2 CO 3

6. L ook at the formula for the molecule N ame as an acid. Is there an oxygen present in the compound? N ame the first element in the molecule, Use a prefix of the number is greater than one. To name the second element, indicate the number (subscript) by using a prefix + change the root to end in -ide. D oes the compound form an acidic aqueous solution? NO YES R oot of the oxyanion present - -ic if oxyanion ends in -ate, or = -ous if oxyanion ends in ite, then acid H ydro- + root of second element + -ic then acid. NO