February 10, 2014 (E)

1. February 10, 2014 (E) • 1-5, write electron configuration and identify valence electrons • Li • N • F • Cl • Fe • What is electronegativity? • What is an example of a direct relationship and an indirect relationship (hint: frequency, wavelength, and energy) • http://www.npr.org/blogs/codeswitch/2014/02/11/275330069/george-washington-carver-the-black-history-monthiest-of-them-all

2. February 12, 2014 (E) • What are covalent bonds? • What is the difference between the two types of covalent bonds? • How are covalent bonds different from ionic bonds? • The distance between the nucleus of atom A and atom B is called the… • The energy released when atom A and atom B join together is the… • What is the relationship between the answer from #4 and #5? • pick up work and exam

3. February 17, 2014 (E) • 1. What does the purple line indicate? • 2. What does the letter “r” indicate? • 3. Which letter represents the shortest bond length? • 4. Which letter represents the highest bond energy? • 5. Which letter represents the highest stability? • 6. Which letter represents the longest bond length? • 7. Based on the graph, what can you conclude about the relationship between bond length and bond energy? A D C B

4. February 19, 2014 (E) • Name the compound: NaCl • How many sodium atoms in the compound? • How many chlorine atoms in the compound? • What is the molar mass of the compound? • What is the relationship between bond length, bond energy, and stability? • How might you answer #5 using a graph, like last week’s warmup?

5. February 20, 2014 (O) • The two types of covalent bonds are… • How are the two types different? • What determines type? • What does a high electronegativity value tell us about an atom? • What is a resonance structure? • Draw the two resonance structures for O3

6. February 20, 2014 (O) • AGENDA • Naming Covalent Compounds • Properties of Covalent Compounds • Applying Geometry to Covalent Compounds • Review Chapter • HOMEWORK • Handout • 1936

10. Covalent Bonds • What are they? • How they are made • Types of Covalent Bonds • Lewis Structures • Naming Covalent Bonds • Calculations • Properties of Covalent Bonds • Shapes of Covalent Bonds

11. Covalent Bonds • OBJECTIVE: Understand what they are

12. Co-valent

13. 1. What are Covalent Bonds? • Covalent Bond = bonds when atoms • share • valence electrons

14. 1. What are Covalent Bonds? • Covalent Bond = bonds when atoms • SHARE • valence electrons • video

15. Difference between Ionic and Covalent Bonds Covalent Atoms gain or lose electrons Atoms share electrons Ionic

16. 1. What are Covalent Bonds? • Most compounds = covalent bonds

17. 1. What are Covalent Bonds? • Most compounds = covalent bonds

18. 1. What are Covalent Bonds? • Most compounds = covalent bonds

19. 1. What are Covalent Bonds? • Most compounds = covalent bonds

20. How Covalent Bonds Form • OBJECTIVE: • Energy • and • formation • of • CB

21. 2. How they are made

22. 2. How they are made • Atom • Nucleus

23. 2. How they are made • Atom • Nucleus

24. 2. How they are made • So how close can they get? • Depends on atomic radius and energy • IMPORTANT: all things want • High STABILTY • Low ENERGY

25. 2. How they are made Purple Line = Energy r = distance

26. 2. How they are made Very high energy Very low stability Moderate energy Low stability Low energy as 432 kJ energy given away, resulting in high stability

27. Very high energy Very low stability Moderate energy Low stability • Bond length = distance between nucleus of bonded atoms Low energy as 432 kJ energy given away, resulting in high stability

28. Very high energy Very low stability Moderate energy Low stability • Bond energy = energy given off when bonds are made • AND • energy needed to add to break bonds Low energy as 432 kJ energy given away, resulting in high stability

29. Very high energy Very low stability Moderate energy Low stability • Graph the relationship between bond length and bond energy Low energy as 432 kJ energy given away, resulting in high stability

30. Sample Question • Based on the data above, what can you conclude about the relationship between bond energy and bond length. Cite data from above to support your answer.

31. WARMUP PAPER: #1, 4, 10

32. 3. Types of Covalent Bonds • 2 types • Nonpolar Covalent • valence electrons EQUALLY shared • Polar Covalent • valence electrons NOT equally shared

33. 3. Types of Covalent Bonds • Electronegativity determines type

34. 3. Types of Covalent Bonds • Higher the number, the more “selfish”

35. 3. Types of Covalent Bonds • Difference > 0.5 Difference > 2.1 • Polar Ionic • Least Ionic Most Ionic

36. 3. Types of Covalent Bonds

37. HOMEWORK: #3, 6, 11, 12,14 • 11. Order from most to least polar

38. 4. Lewis Dot Structures • OBJECTIVE: • Determine • potential number • of bonds

39. 4. Lewis Dot Structures • Which orbital diagram is correct? • A B

40. 4. Lewis Dot Structures • What is a Lewis Dot Structure? • dot = valence electron

41. 4. Lewis Dot Structures • dot = valence electron

42. 4. Lewis Dot Structures • .. • Octet Rule: • be like noble gases with 8 dots • H is an exception, • more exceptions later

43. 4. Lewis Dot Structures • List elements • Draw dots • Carbon usually in the center • If there is no Carbon, the atom with LOWEST electronegativity • Draw bonds • Distribute electrons

44. 4. Lewis Dot Structures • Patterns? • # of bonds = # UNPAIRED dots • Ex: • Cl has 7 dots, of which 1 is… • Oxygen has 6 dots, of which 2 are.. • Nitrogen has 5 dots, of which 3.. • Carbon has 4 dots, and all 4 are…

45. 4. Lewis Dot Structures

46. 4. Lewis Dot Structures Exceptions to the Octet Rule Less than 8 More than 8 Polyatomic Ions

47. 4. Lewis Dot Structures Exceptions to the Octet Rule Less than 8 Beryllium and Boron BeCl2 BCl3

48. 4. Lewis Dot Structures Exceptions to the Octet Rule 2. More than 8 Sulfur and Xenon SF6 XeF4

49. 4. Lewis Dot Structures Exceptions to the Octet Rule 3. Polyatomic Ions Cations Anions REMOVE electrons ADD electrons add brackets [ ]

50. 4. Lewis Dot Structures Resonance = 2 or more possible Lewis Dot Structures