1. Review What is a valence electron? A.Electrons at the core of an atom B.Electrons at the outermost shell of an atom C.Electrons at the outermost shell of an atom that take part in chemical reactions D.I don’t remember…

2. Review How do you count valence electrons for s and p block elements (groups 1, 2, 13-18)? A.Count all electrons in all orbitals outside the core B.Count only the electrons in the s and p orbitals C.Count only the electrons in the s and p orbitals with the same n value D.Count only the electrons in the s and p orbitals with the highest n value

3. Review How do you count valence electrons d block elements (groups 3-12)? A.Count all electrons in all orbitals with the highest n value B.Count the electrons in the s, p, d orbitals C.Count only the electrons in the s and p orbitals with the highest n value D.Count only the electrons in the s and p orbitals with the highest n value, and any partially filled d orbitals

4. Review For negative ions, add the extra electrons in the… A.s-orbital always B.p-orbital always C.d-orbital always D.Whichever orbital that isn’t full yet

5. Review For positive ions, take away the extra electrons from the… A.highest p-orbital first, then s, then d if necessary B.highest s-orbital first, then p, then d C.highest p-orbital first, then d, then s D.noble gas core

6. The Periodic Table

12. Period: horizontal row on the periodic table (left  right)

13. Family or Group: vertical column on the periodic table (up & down) elements in a column share similar properties

14. The Families on the Periodic Table

15. Hydrogen

16. Alkali Metals

17. Alkaline Earth Metals

18. Transition Metals

19. Halogens

20. Noble Gases

22. Want your bad romance

23. 8.7 – Atomic Radii

24. Across a period, the atomic radius _________________ because the ___________________________________ the number of protons increases force of attraction from protons increases  electrons move closer e-e- + + e-e- + + + e-e- e-e- e-e- I have cookies force of attraction from protons increases electrons move closer  smaller radii the #p increases decreases

25. 8.7 – Atomic Radii Down a group, the atomic radius __________________ because the ___________________________________ the number of electrons also increases increasing electron-electron repulsion inner electrons shields outer electrons from the pull of the nucleus electrons occupy orbitals that are increasingly further away from the nucleus (gain in shells) increases

26. Atomic Radii

27. Down a group, the atomic radius __________________ because the ___________________________________ more shells = bigger size the number of electrons also increases, ___________________________________ ___________________________________ increases # of shells increases creating electron-electron repulsion and electron shielding

28. Atomic Radii e-e- + + e-e- + + + e-e- e-e- e-e- Oh dude, personal space Excuse me, but you’re like, totally in my bubble

29. Atomic Radii e-e- + + e-e- + + + e-e- e-e- e-e-

30. e-e- + + e-e- + + + e-e- e-e- e-e-

32. Which is bigger? Ca Co

33. Which is bigger? Mg Al

34. Which is bigger? Ba Ca

35. Which is bigger? Li Ba

36. Example: Consider the following pairs of atoms. Which atom has the larger atomic radius? a)O or O 2- ? 2 e - are added in O 2- effect of positive charge from the nucleus distributed among 2 additional e - in O 2- increased electron-electron repulsion in O 2- O 2- is larger

37. Example: Consider the following pairs of atoms. Which atom has the larger atomic radius? b) Ca and Ca 2+ 2 e - are lost in Ca 2+ nucleus has 2 less electrons to pull in Ca 2+  remaining electrons feel stronger pull decreased electron-electron repulsion in Ca 2+ Ca is larger

38. Example: Arrange the following species in order of increasing size. Rb + Y 3+ Br - Kr Sr 2+ Se 2- the species are all isoelectronic with Kr Species# p# e - Order of Increasing size Rb + Y 3+ Br - Kr Sr 2+ Se 2-

40. Example: Arrange the following species in order of increasing size. Rb + Y 3+ Br - Kr Sr 2+ Se 2- the species are all isoelectronic with Kr Species# p# e - Order of Increasing size Rb + Y 3+ Br - Kr Sr 2+ Se 2-

41. Example: Arrange the following species in order of increasing size. Rb + Y 3+ Br - Kr Sr 2+ Se 2- the species are all isoelectronic with Kr Species# p# e - Order of Increasing size Rb + 37363 Y 3+ 39361 Br - 35365 Kr36 4 Sr 2+ 38362 Se 2- 34366

43. Consider this: Which has a larger effect on atomic radii, a change in the number of protons, or a change in the number of electrons?

46. Which is the biggest? NaMo Ra

47. Which is the biggest? NaNa +

48. Which is the biggest? CrCr 3+

49. Which is the smallest? CrCr 3+ Cr 2+

50. Which is the smallest? FF-F-

51. Arrange the following in order of increasing atomic radii. Na, Mg, K, F F < Mg < Na < K

52. Arrange the following in order of increasing atomic radii. K, Cu, Br, Rb Br < Cu < K < Rb

53. Arrange the following in order of increasing atomic radii. Na, Ca 2+, P, P 3- Ca 2+ < P < Na < P 3-

54. 8.8 – Ionization Energy Ionization energy: the energy needed _______________________from a neutral atom The harder it is to remove the e -, the _______ the IE to remove a valence e - higher

55. 1.Generally speaking, what happens to IE 1 as you go across a period and why?

56. IE 1 increases # p increases so valence e - are held tighter, thus are more difficult to remove

57. 2.What explains the high IE 1 for noble gases?

58. stable full outer shell high #p 3.How does IE 2 compare with IE 1 ? IE 2 is higher once an e - is removed from a neutral atom, the atom becomes +charged  remaining e - feel stronger pull from nucleus atomic radii decreases after first ionization

59. 4.What happens to IE as you go down a group and why? IE decreases atomic radii increases so valence e - are held less tightly

60. 5.What explains the decrease in IE 1 from Be to B and Mg to Al?

61. Be: 1s 2 2s 2 Mg: 1s 2 2s 2 2p 6 3s 2 B: 1s 2 2s 2 2p 1 Al: 1s 2 2s 2 2p 6 3s 2 3p 1 additional subshell added  distance between nucleus and valence electron increases, more electron shielding

62. 8.9 – Electronegativity Electronegativity: an atom’s ability to attract electrons moving across a period: increases #p increases Atomic radii decreases: distance from nucleus to valence e - of another atom decreases moving down a group: decreases atomic radii increases: distance from nucleus to valence e - of another atom increases

64. What Can You Say About Reactivity?

66. Example: Circle the most reactive element in each list. a)Li Na K b)Zn Cs K c)N F Br

67. Example: Circle the most reactive element in each list. a)Li Na K b)Zn Cs K c)N F Br

68. Example: Circle the most reactive element in each list. a)Li Na K b)Zn Cs K c)N F Br

69. Example: Circle the element that is more metallic in each list. a)Cr K Ti b)Nb Ta V c)Ca Mg Be

70. Example: Circle the element that is more metallic in each list. a)Cr K Ti b)Nb Ta V c)Ca Mg Be

71. Example: Circle the element that is more metallic in each list. a)Cr K Ti b)Nb Ta V c)Ca Mg Be