2. 1 Covalent Bonding Sharing is caring

3. 2 Metallic Ionic Covalent Transfer Electrons Delocalized Electrons (sea of e - ) Share Electrons Molecule Unit Cell

4. 3 In covalent bonding, atoms still want to achieve a noble gas configuration (the octet rule). But rather than losing or gaining electrons, atoms share electrons.

5. 4 Covalent Bonds When one nonmetal shares one or more electrons with an atom of another nonmetal so both atoms end up with eight valence electrons

6. 5 But rather than losing or gaining electrons, atoms now share an electron pair. The shared electron pair is called a bonding pair

7. 6 Naming Covalent Compound

8. 7 Covalent bonding Makes molecules Specific atoms joined by sharing electrons Two kinds of molecules: Molecular compound Sharing by different elements Diatomic molecules Two of the same atom O 2 N 2

9. 8 Diatomic elements There are 7 elements that always form molecules: H 2, N 2, O 2, F 2, Cl 2, Br 2, I 2 The –gens (hydrogen, nitrogen, oxygen and halogens)   NEVER FOUND AS SINGLE ATOMS if “alone”   Their names are just the name of the element   Oxygen by itself means O 2

10. 9 1 and 7 Covalent Bond Video

11. 10 Binary Molecular Compounds Steps to name compounds a. a.Name first element - use entire name b. b.Name second element- change ending to –ide c. c.Prefixes used to indicate number of each atom d. Only time that no prefix is used is if the first is a one   Examples: CCl 4 – As 2 O 3 – tri di tetrachloride carbon arsenic oxide

12. 11 The Prefixes Mono-monocle Tri-tricycle Penta-pentagon Octa- octopus Tetra-Tetris Di-Dialogue

13. 12 1mono 2di 3tri 4tetra 5penta 6hexa 7hepta 8octa 9nona 10deca The first vowel is often dropped to avoid the combination of “ao” or “oo”. CO = carbon monoxide (monooxide) SO 2 = sulfur dioxide (doxide) P 4 O 10 = tetraphosphorus decoxide

14. 13 CF 4 N 2 O SF 6 carbon tetraflouride dinitrogen monoxide sulfur hexafluoride Molecular Nomenclature: Examples P2O3P2O3 diphosporus trioxide IF 7 iodine heptafluoride

15. 14 arsenic trichloride dinitrogen pentoxide tetraphosphorus decoxide AsCl 3 N 2 O 5 P 4 O 10 More Molecular Examples

16. 15   Octet Rule: All elements will have 8 electrons around it through a combination of shared and unshared electrons. THERE ARE A FEW EXCEPTIONS!!! »H »H only needs 2 electrons »Be »Be only needs 4 electrons »B »B only needs 6 electrons Covalent Bonds and Lewis Structures

17. 16 Most covalent bonds involve the sharing of: –2 electrons (single covalent bond), –4 electrons (double covalent bond, or –6 electrons (triple covalent bond). Covalent Bonds and Lewis Structures

18. 17 Covalent Bonds and Lewis Structures We are going to use the N.A.S method: N = needed A = available S = shared (or halogens) HONC 1234 # of bonds * * Element that form the most bonds goes in the middle

19. 18 Covalent Bonds and Lewis Structures  O 2 :  N =  A =  S = 2 (8) = 16 6 + 6= 12 16 – 12 = 4 (2 bonds)

20. 19 Covalent Bonds and Lewis Structures  CO:  N =  A =  S = 8 + 8 = 16 4 + 6= 10 16 – 10 = 6 (3 bonds)

21. 20   Lewis structures (electron dot structures) show the structure of molecules. (Bonds can be shown with dots for electrons, or with dashes: 1 dash = 2 electrons)  H 2 HBr  CCl 4  N 2

22. 21   Lewis structures (electron dot structures) show the structure of molecules. (Bonds can be shown with dots for electrons, or with dashes: 1 dash = 2 electrons)  H 2 HBr  CCl 4  N 2

23. 22   Lewis structures (electron dot structures) show the structure of molecules. (Bonds can be shown with dots for electrons, or with dashes: 1 dash = 2 electrons)  H 2 HBr  CCl 4  N 2

24. 23   Lewis structures (electron dot structures) show the structure of molecules. (Bonds can be shown with dots for electrons, or with dashes: 1 dash = 2 electrons)  H 2 HBr  CCl 4  N 2

25. 24   Lewis structures (electron dot structures) show the structure of molecules. (Bonds can be shown with dots for electrons, or with dashes: 1 dash = 2 electrons)  H 2 HBr  CCl 4  N 2

26. 25   Lewis structures (electron dot structures) show the structure of molecules. (Bonds can be shown with dots for electrons, or with dashes: 1 dash = 2 electrons)  H 2 HBr  CCl 4  N 2

27. 26 Covalent Bonds and Lewis Structures  NO 3 - :  N =  A =  S = 8 + 3 (8) = 32 5 + 3 (6) + 1= 24 32 – 24 = 8 (4 bonds)