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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.
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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
Name each of the following molecules: CCl4 Carbon tetrachloride NF3 nitrogen trifluoride CO Carbon monoxide As2O3 Diarsenic trioxide S4N4 Tetrasulfur tetranitride SiF4 Silicon tetrafluoride SO2 Sulfur dioxide
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. HCl Hydrochloric acid H3P Hydrophosphic acid HF Hydrofluoric acid HI Hydroiodic acid H2S Hydrosulfuric acid
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. H2SO4 Sulfuric acid HClO2 Chlorous acid HClO3 Chloric acid H3PO4 Phosphoric acid H2SO3 Sulfurous acid HNO3 Nitric acid
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 acid H3N Boric acid H3BO3 Acetic Acid HC2H3O2 Hypochlorous acid HClO Carbonic acid H2CO3
Look at the formula for the molecule Name 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. Does the compound form an acidic aqueous solution? NO YES Name as an acid. Is there an oxygen present in the compound? Root of the oxyanion present - -ic if oxyanion ends in -ate, or = -ous if oxyanion ends in ite, then acid YES NO Hydro- + root of second element + -ic then acid.