1. CHEMISTRY LAB C Team of 2 students 50 minutes Safety Requirements Wear apron or lab coat OSHA approved goggles with indirect vents Do not bring reference material or calculators

2. CHEMISTRY LAB C A series of stations with various activities Could Include:  Hands-on Activities: Experiments  Interpretation of Experimental Data –(graphs, charts, diagrams, data tables, etc.)  Observation of Running Demonstration Redox Reactions & Periodicity

3. Periodicity Understand the periodic nature of the elements Demonstrated Conceptually Predicting and explaining trends Demonstrated Experimentally Collecting and/or accounting for data

4. Topics Covered Physical Properties Electronic Structure and Bonding Chemical Properties

5. Physical Properties Atomic and Ionic Radii Ionization Energy Melting Point Electronegativity

6. Electronic Structure Electron Configuration Ionic and Covalent Bonding Charges on Ions Metallic Properties

7. Chemical Properties Precipitation Formation (Solubility) Reaction with Acids Acidity of Oxides

8. Dmitri Mendeleev Periodic Properties Arrange Elements According to Properties Families have similar properties –All alkali metals react with water –But to different degrees or reactivity Predict Ekasilicon between Si and Sn Later arranged according to atomic number not mass

10. Electron Configuration - I H 1s 1 He 1s 2 [He] Li 1s 2 2s 1 [He] 2s 1 Be 1s 2 2s 2 [He] 2s 2 B 1s 2 2s 2 2p 1 [He] 2s 2 2p 1 C 1s 2 2s 2 2p 2 [He] 2s 2 2p 2 N 1s 2 2s 2 2p 3 [He] 2s 2 2p 3 O 1s 2 2s 2 2p 4 [He] 2s 2 2p 4 F 1s 2 2s 2 2p 5 [He] 2s 2 2p 5 Ne 1s 2 2s 2 2p 6 [He] 2s 2 2p 6 = [Ne]

11. Electron Configuration - II Na [Ne] 3s 1 Mg [Ne] 3s 2 Al [Ne] 3s 2 3p 1 Si [Ne] 3s 2 3p 2 P [Ne] 3s 2 3p 3 S [Ne] 3s 2 3p 4 Cl [Ne] 3s 2 3p 5 Ar [Ne] 3s 2 3p 6 == [Ar]

12. Order of Electron Filling 7s 7p 6s 6p 6d 5s 5p 5d 5f 4s 4p 4d 4f 3s 3p 3d 2s 2p 1s

14. Electron Configuration - III K [Ar] 4s 1 Ca [Ar] 4s 2 Or this order is OK ! Sc [Ar] 4s 2 3d 1 [Ar] 3d 1 4s 2 Ti [Ar] 4s 2 3d 2 [Ar] 3d 2 4s 2 V [Ar] 4s 2 3d 3 [Ar] 3d 3 4s 2 Cr [Ar] 4s 1 3d 5 Mn [Ar] 4s 2 3d 5 Fe [Ar] 4s 2 3d 6 Either order will be OK ! Co [Ar] 4s 2 3d 7 But it’s normally best to Ni [Ar] 4s 2 3d 8 put the one filling last!!! Cu [Ar] 4s 1 3d 10 Zn [Ar] 4s 2 3d 10 Anomalies to Filling Anomalies to Filling

15. Orbital Box Diagrams - III Na Ar Atomic Number Orbital Box Condensed Electron Element Diagrams(3s&3p) Configuration 11 Na [He] 3s 1 12 Mg [He] 3s 2 13 Al [He] 3s 2 3p 1 14 Si [He] 3s 2 3p 2 15 P [He] 3s 2 3p 3 16 S [He] 3s 2 3p 4 17 Cl [He] 3s 2 3p 5 18 Ar [He] 3s 2 3p 6 3s 3p x 3p y 3p x 3p z

16. Orbital Box Diagram - IV : Sc Zn 4s 3d Z = 21 Sc [Ar] 4s 2 3d 1 Z = 22 Ti [Ar] 4s 2 3d 2 Z = 23 V [Ar] 4s 2 3d 3 Z = 24 Cr [Ar] 4s 1 3d 5 Z = 25 Mn [Ar] 4s 2 3d 5 Z = 26 Fe [Ar] 4s 2 3d 6 Z = 27 Co [Ar] 4s 2 3d 7 Z = 28 Ni [Ar] 4s 2 3d 8 Z = 29 Cu [Ar] 4s 1 3d 10 Z = 30 Zn [Ar] 4s 2 3d 10

17. Electronic Configuration Ions Na 1s 2 2s 2 2p 6 3s 1 Na + 1s 2 2s 2 2p 6 Mg 1s 2 2s 2 2p 6 3s 2 Mg +2 1s 2 2s 2 2p 6 Al 1s 2 2s 2 2p 6 3s 2 3p 1 Al +3 1s 2 2s 2 2p 6 O 1s 2 2s 2 2p 4 O - 2 1s 2 2s 2 2p 6 F 1s 2 2s 2 2p 5 F - 1 1s 2 2s 2 2p 6 N 1s 2 2s 2 2p 3 N - 3 1s 2 2s 2 2p 6

18. Fig. 8.23

19. Atomic Size

20. Across a row Diameter Decreases Electrons added to the same shell More protons pull in electrons closer Down a column Diameter Increases Electrons fill into further out shells

21. Fig. 8.13

23. Transition Metals Across the transition series (d block) the atomic radii initially decrease, then increase. Initially, the increase in the nuclear charge decreases the size when d electrons are added into a shell closer than the valence shell. Later the increased electron - electron repulsion from many electrons in the d orbitals cause the atomic radii to increase.

25. Law of Dulong and Petit Heat Capacity is the amount of energy needed to raise the temperature of an amount of a substance 1819 Pierre Dulong and Alexis Petit Product of molar mass and heat capacity is a constant for metals Heat capacity decreases with molar mass

26. Ionization Energy The energy required to remove an electron from a neutral atom A + energy  A + + e -

27. Second Ionization Energy The energy required to remove an electron from a +1 cation A + + energy  A 2+ + e - Successive ionization energies are greater than earlier ionization energies

29. Periodicity of First Ionization Energy (IE 1 ) Fig. 8.14

31. Fig. 8.27

32. Size of Ions Size of anions are larger than atoms Adding electrons to an atom increases the size: Higher -/+ ratio Size of cations are smaller than atoms Removing electrons from an atom decreases the size: Lower -/+ ratio and often lose electrons in furthest shell

34. Crystal Structures Ionic Crystals are lattice of large anions with smaller cations inbetween the anions (r+ / r-) > 0.732 cations in cubic hole 0.732 > (r+ / r-) > 0.414 cations in octahedral holes 0.414 > (r+ / r-) cations in tetrahedral holes

35. Crystal Structures CsCl (r+ / r-) = 0.169 nm/0.181nm > 0.732 cations in cubic hole BCC NaCl (r+ / r-) = 0.095 nm/0.181nm 0.732 > (r+ / r-) > 0.414 cations in octahedral holes FCC ZnS (r+ / r-) = 0.074 nm/0.184nm 0.414 > (r+ / r-) cations in tetrahedral holes FCC

36. Electron Affinity Energy released when an electron is added to a neutral atom A + e -  A - + energy (Sometimes defined as energy needed to remove an electron from an anion)

37. More Negative

38. Trends in Three Atomic Properties Fig 8.18

39. Fig. 9.2

40. Metals and Nonmetals Metals Shiny luster, various colors - mostly silver Malleable and ductile Good conductors of heat and electricity Most metal oxides are basic Na 2 O(s) + H 2 O(l) ==> 2 NaOH(aq) Generally form cations

41. Metals and Nonmetals Nonmetals No luster, various colors Usually brittle - some hard, some soft Poor conductors of heat and electricity Most nonmetallic compounds are acidic CO 2 (g) + H 2 O(l) ==> H 2 CO 3 (aq) Generally form anions or oxyanions

42. Metalloids (Semimetals) Intermediate properties between metals and nonmetals Some metallic characteristics and some nonmetal characteristics Some, most notably Si, are electrical semiconductors

44. Lattice Energy Li + (g) + F - (g) ==> LiF (s)  H o Lattice of LiF = -1050 kJ

45. Periodic Trends in Lattice Energy Electrostatic Force = (C + ) (A - ) / Distance Ionic Size Ionic Charge

46. Melting and Boiling Points of Some Ionic Compounds Compound mp( o C) bp( o C) CsBr 636 1300 NaI 661 1304 MgCl 2 714 1412 KBr 734 1435 CaCl 2 782 >1600 NaCl 801 1413 LiF 845 1676 KF 858 1505 MgO 2852 3600 Table 9.1 (p. 340)

47. Electronegativity A scale to show the relative attraction of an atom for electrons shared in a bond Linus Pauling Scale Lowest Fr = 0.7 Highest F = 4.0

49. The Periodic Table of the Elements 2.1 0.91.5 0.91.2 0.81.01.3 0.8 0.7 1.0 0.9 1.51.6 1.51.8 1.2 1.1 1.8 1.91.6 1.41.6 1.5 1.8 1.7 1.9 2.2 1.9 2.4 1.7 1.9 2.02.53.03.54.0 He Ne Ar1.51.82.12.53.0 1.61.82.02.42.8Kr Xe Rn 2.52.1 2.2 1.9 2.01.9 1.81.7 1.8 1.1 1.3 1.2 1.3 1.51.71.3 1.5 0.9 1.32.2 Electronegativity 1.1 Th Pa U Np No Lr 1.3 Ce Pr Nd PmYb Lu

50. Bond Polarity Nonpolar Covalent Bonds: Electronegativity Difference is ideally 0 Very small differences are still considered to be mostly covalent bonds, up to about 0.4 Polar Covalent Bonds: Electronegativity Difference measurable Has polar covalent characteristics up to 2.0 Mostly Ionic Bonds: High Electronegativity Differences

51. Bond Polarity Cl 2 is a nonpolar covalent bond  E = (3.0 - 3.0) = 0 HCl is a polar covalent bond  E = (3.0 - 2.1) = 0.9 NaCl is a very polar bond - ionic  E = (3.0 - 0.9) = 2.1

52. The Redox Process in Compound Formation Fig. 4.13

53. Oxidation-Reduction Reactions How can we predict if a oxidation-reduction reaction will occur Experimental trials give reactivity relationships

54. Metal Activity Higher activity More the metal wants to be oxidized More the metal wants to gain electrons Better reducing agent Compare to other metals Compare to H + in water and acids

56. Activity Series Mg ==> Mg 2+ has a higher activity than Zn ==> Zn 2+ Therefore: Mg + Zn 2+ ==> Mg 2+ + Zn and Zn + Mg 2+ ==> No Reaction

57. Activity Series Cr ==> Cr 3+ has a higher activity than Ni ==> Ni 2+ Therefore: 2Cr + 3Ni 2+ ==> 2Cr 3+ + 3Ni and Ni + Cr 3+ ==> No Reaction

58. Basic and Acidic Oxides More ionic oxides formed on left side of periodic table If dissolve in water form basic solutions MO(s) + H 2 O(l)  M +2 (aq) + 2 OH - (aq)

59. Basic and Acidic Oxides More covalent oxides formed on right side of periodic table If dissolve in water form acidic solutions MO(g) + H 2 O (l)  H 2 MO 2 (aq) H 2 MO 2 (aq) +H 2 O  H 3 O + (aq) + HMO 3 - (aq)