Covalent bonding

1. Covalent bonding Grade 9 Chemistry

2. Starter • What ions do Chlorine form? • Imagine you have 2 chlorine ions – how could they help EACH OTHER to reach a stable state? • It might help if you draw out the Lewis structures for 2 chlorine ions!

3. LET’S FIRST REVIEW IONIC BONDING

4. K F In an IONIC bond, electrons are lost or gained, resulting in the formation of IONS in ionic compounds.

5. K F

6. K F

7. K F

8. K F

9. K F

10. K F

11. _ + K F

12. _ + K F The compound potassium fluoride consists of potassium (K+) ions and fluoride (F-) ions

13. _ + K F The ionic bond is the attraction between the positive K+ ion and the negative F- ion

14. So what are covalent bonds?

15. In covalent bonding, atoms still want to achieve a noble gas configuration (the octet rule).

16. In covalent bonding, atoms still want to achieve a noble gas configuration (the octet rule). But rather than losing or gaining electrons, atoms now share an electron pair.

17. In covalent bonding, atoms still want to achieve a noble gas configuration (the octet rule). But rather than losing or gaining electrons, atoms now share an electron pair. The shared electron pair is called a bonding pair

18. Chlorine forms a covalent bond with itself Cl2

19. How will two chlorine atoms react? Cl Cl

20. Cl Cl Each chlorine atom wants to gain one electron to achieve an octet

21. Cl Cl Neither atom will give up an electron – chlorine is highly electronegative. What’s the solution –what can they do to achieve an octet?

22. Cl Cl

23. Cl Cl

24. Cl Cl

25. Cl Cl

26. Cl Cl octet

27. Cl Cl octet circle the electrons for each atom that completes their octets

28. Cl Cl The octet is achieved by each atom sharing the electron pair in the middle circle the electrons for each atom that completes their octets

29. Cl Cl The octet is achieved by each atom sharing the electron pair in the middle circle the electrons for each atom that completes their octets

30. Cl Cl This is the bonding pair circle the electrons for each atom that completes their octets

31. Cl Cl It is a single bonding pair circle the electrons for each atom that completes their octets

32. Cl Cl It is called aSINGLE BOND circle the electrons for each atom that completes their octets

33. Cl Cl Single bonds are abbreviated with a dash circle the electrons for each atom that completes their octets

34. Cl Cl This is the chlorine molecule, Cl2 circle the electrons for each atom that completes their octets

35. O2 Oxygen is also one of the diatomic molecules

36. O O How will two oxygen atoms bond?

37. O O Each atom has two unpaired electrons

38. O O

39. O O

40. O O

41. O O

42. O O

43. O O

44. O O Oxygen atoms are highly electronegative. So both atoms want to gain two electrons.

45. O O Oxygen atoms are highly electronegative. So both atoms want to gain two electrons.

46. O O

47. O O

48. O O

49. O O

50. O O Both electron pairs are shared.