Naming Covalent Compounds

1. Naming Covalent Compounds Naming and Writing Covalent Formulas NO nitrogen oxide NO2 nitrogen dioxide N2O4 dinitrogen tetroxide

2. Guide to Naming Covalent Compounds with Two Nonmetals

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 NO2 nitrogen dioxide N2O dinitrogen oxide N2O4 dinitrogen tetroxide N2O5 dinitrogen pentoxide

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 3prefixes to indicate the number (from subscripts) of atoms of each nonmetal. (Monois usually omitted from the first element, sometimes from the second.)

5. Naming Covalent Compounds (Continued) What is the name of SO3? 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. SO3→ sulfur trioxide The subscript 1(for S) or mono is understood.

6. Naming Covalent Compounds (Continued) Name P4S3 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 astetra. The subscript 3 of O is shown as tri. P4S3→tetraphosphorus trisulfide

7. Formulas and Names of Some Covalent Compounds

8. Flowchart for Naming Covalent Compounds with Two Nonmetals

9. Learning Check Select the correct name for each compound. A. SiCl4 1) silicon chloride 2) tetrasilicon chloride 3) silicon tetrachloride B. P2O5 1) phosphorus oxide 2) phosphorus pentoxide 3) diphosphorus pentoxide C. Cl2O7 1) dichlorine heptoxide 2) dichlorine oxide 3) chlorine heptoxide

10. Solution Select the correct name for each compound. A. SiCl4 3) silicon tetrachloride B. P2O5 3) diphosphorus pentoxide C. Cl2O7 1) dichlorine heptoxide

11. Learning Check Write the name of each covalent compound. CO _____________________ CO2 _____________________ PCl3 _____________________ CCl4 _____________________ N2O _____________________

12. Solution Write the name of each covalent compound. CO carbon monoxide CO2 carbon dioxide PCl3 phosphorus trichloride CCl4 carbon tetrachloride N2O dinitrogen oxide

13. Guide to Writing Formulas for Covalent Compounds

14. Writing Formulas of Covalent Compounds 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: CS2

15. Learning Check Write the correct formula for each of the following: A. phosphorus pentachloride B. dinitrogen trioxide C. sulfur hexafluoride

16. Solution Write the correct formula for each of the following: A. phosphorus pentachloride 1P penta = 5Cl PCl5 B. dinitrogen trioxide di = 2N tri = 3 O N2O3 C. sulfur hexafluoride 1S hexa = 6F SF6