General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 1 Naming Covalent Compounds Naming and Writing Covalent Formulas NO nitrogen oxide NO 2 nitrogen dioxide N 2 O 4 dinitrogen tetroxide

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. Guide to Naming Covalent Compounds with Two Nonmetals 2

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 3 Names of Covalent Compounds Prefixes are used  in the names of covalent compounds  because two nonmetals can form two or more different compounds Examples of compounds of N and O: NO nitrogen oxide NO 2 nitrogen dioxide N 2 O dinitrogen oxide N 2 O 4 dinitrogen tetroxide N 2 O 5 dinitrogen pentoxide

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 4 Naming Covalent Compounds STEP 1 Name the first nonmetal by its element name. STEP 2 Name the second nonmetal with an ide ending. STEP 3 prefixes to indicate the number (from subscripts) of atoms of each nonmetal. (Mono is usually omitted from the first element, sometimes from the second.)

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 5 What is the name of SO 3 ? STEP 1 The first nonmetal is S sulfur. STEP 2 The second nonmetal is O, named oxide. STEP 3 The subscript 3 of O is shown as the prefix tri. SO 3 → sulfur trioxide The subscript 1(for S) or mono is understood. Naming Covalent Compounds (Continued)

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 6 Name P 4 S 3 STEP 1 The first nonmetal P is phosphorus. STEP 2 The second nonmetal S is sulfide. STEP 3 The subscript 4 of P is shown as tetra. The subscript 3 of O is shown as tri. P 4 S 3 → tetraphosphorus trisulfide Naming Covalent Compounds (Continued)

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 7 Formulas and Names of Some Covalent Compounds

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. Flowchart for Naming Covalent Compounds with Two Nonmetals 8

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 9 Select the correct name for each compound. A.SiCl 4 1) silicon chloride 2) tetrasilicon chloride 3) silicon tetrachloride B. P 2 O 5 1) phosphorus oxide 2) phosphorus pentoxide 3) diphosphorus pentoxide C.Cl 2 O 7 1) dichlorine heptoxide 2) dichlorine oxide 3) chlorine heptoxide Learning Check

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 10 Select the correct name for each compound. A.SiCl 4 3) silicon tetrachloride B. P 2 O 5 3) diphosphorus pentoxide C.Cl 2 O 7 1) dichlorine heptoxide Solution

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 11 Write the name of each covalent compound. CO_____________________ CO 2 _____________________ PCl 3 _____________________ CCl 4 _____________________ N 2 O_____________________ Learning Check

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 12 Write the name of each covalent compound. CO carbon monoxide CO 2 carbon dioxide PCl 3 phosphorus trichloride CCl 4 carbon tetrachloride N 2 Odinitrogen oxide Solution

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. Guide to Writing Formulas for Covalent Compounds 13

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 14 Write the formula for carbon disulfide. STEP 1 Elements are C and S STEP 2 No prefix for carbon means 1 C Prefix di = 2 Formula: CS 2 Writing Formulas of Covalent Compounds

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 15 Write the correct formula for each of the following: A. phosphorus pentachloride B. dinitrogen trioxide C. sulfur hexafluoride Learning Check

General, Organic, and Biological Chemistry Copyright © 2010 Pearson Education, Inc. 16 Write the correct formula for each of the following: A. phosphorus pentachloride 1P penta = 5ClPCl 5 B. dinitrogen trioxide di = 2N tri = 3 O N 2 O 3 C. sulfur hexafluoride 1S hexa = 6FSF 6 Solution