22: Coordination ChemistryProperties of Transition ElementsProperties of Transition ElementsElectron ConfigurationsElectron ConfigurationsElectron ConfigurationsPracticing Electron ConfigurationsElectron ConfigurationsElectron ConfigurationsTrends in Atomic RadiiTrends in Atomic RadiiOxidation StatesOxidation StatesCoordination ChemistryOxidation StatesOxidation States22: Coordination Chemistry22.1 Properties of the Transition Elements 22.2 Iron and Steel: The Use of Pyrometallurgy22.3 Copper: A Coinage Metal22.4 Silver and Gold: The Other Coinage Metals22.5 Chromium22.6 Coordinate Covalent Bonds22.7 Crystal-Field TheoryFriday, October 31, 2014Read: Section 22.1 for Friday Sections 22.2, 22.3 and 22.4 MondayEnd of Chapter 22 Problems: 8, 14, 16, 18, 20, 21, 22, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 63, 65, 67, 73, 75, 77, 78, 79, 83, 85, 91Friday, October 31, 2014Read: Section 22.1 for Friday Sections 22.2, 22.3 and 22.4 MondayEnd of Chapter 22 Problems: 8, 14, 16, 18, 20, 21, 22, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 63, 65, 67, 73, 75, 77, 78, 79, 83, 85, 91Similar to main-group metals(conduct, ductile/malleable).Differences:Properties of Transition Elements•Elemental forms are silvery-white or bluish (except Au and Cu)•Overall higher m.p. and b.p. (W(tungston called wolfren) : 3410°C•Higher densities (Os: 22.6 g/mL; Ir: 22.7 g/mL)Properties of Transition Elements•Many form brightly-colored compounds and complex ions•Have multiple common oxidation states•Some are paramagnetic (unpaired electrons)•A few are ferromagnetic (a bunch of unpaired electrons and line them up magnet on fridge)K2Cr2O7K2CrO4NiCl2CuSO4Co(NO3)2KMnO4Non-standard configuration is more stable.(½ filled and filled d sublevels are favored)Electron ConfigurationsLa5d1 6s2Sc3d1 4s2Y4d1 5s2Hf4f14 5d2 6s2Ti3d2 4s2Zr4d2 5s2Ta4f14 5d3 6s2V3d3 4s2Nb4d3 5s2W4f14 5d5 6s1Cr3d5 4s1Mo4d5 5s1Re4f14 5d5 6s2Mn3d5 4s2Tc4d5 5s2Os4f14 5d6 6s2Fe3d6 4s2Ru4d6 5s2Ir4f14 5d7 6s2Co3d7 4s2Rh4d7 5s2Pt4f14 5d8 6s2Ni3d8 4s2Pd4d85s2Au4f14 5d10 6s1Cu3d10 4s1Ag4d10 5s1Hg4f14 5d10 6s2Zn3d10 4s2Cd4d10 5s2Lanthanides intervene(4f subshell)Electron ConfigurationsScTiVCrMnFeCoNiCuZn3d 4s 4punpaired e- 1236543210Ion formation:Fe Fe2+Fe3+V4+VV2+•Measured moments confirm that ns are lost first. Electron ConfigurationsPracticing Electron Configurations•What are the electron configurations for Pt2+ and Co3+?Pt2+[Xe] 4f145d8Co3+  [Ar]3d6•How many unpaired electrons are in Cr3+?3 unpaired electronsPay attention to the ions vs. elements (elements are the ones with exceptions)Electron ConfigurationsGouy Balance•Paramagnetic ions have a magnetic moment.•More unpaired e- = higher moment.Electron Configurations•Magnetic moments are slightly higher than the number of unpaired electronsFe3+(Fe:3d64s2)If lost from d: 3d3If lost from s: 3d5Experimental: 5.92= ~5 Unpaired electronsAtomic radii (pm)Atomic radii (pm)Across a period:•Add an e- = add a p+•Larger nuclear charges pull the e- shells in more tightly.•doubly-occupied d orbitals swell (e-/e- repulsion). Down a group:•4th period atoms < 5th (added shell) ≈ 6th (Ln contraction)•Lananide contraction  really dropping radius significantlyTrends in Atomic RadiiTrends in Atomic RadiiExplained by the Lanthanide Contraction•14 f-block elements “hidden” between La and Hf•14 added p+ counteract the growth from the extra shell ( higher Zeff pulls shells tighter) •The 5th and 6th row transition metals have:Almost equal sizeVery similar chemical propertiesOxidation StatesMost have multiple oxidation states. Exceptions:•Scandium group elements are all +3.•Zn and Cd = +2Sc Ti V Cr Mn Fe Co Ni Cu Zn+8+7+6+5+4+3+2+10More commonLess commonOxidation StatesTransition metal ion properties:•High ox. state compounds are strong oxidizing agents. Cr2O72- + 14 H3O+ + 6 e- → 2 Cr3+ + 21 H2O•Within the same element: Low ox. states are ionic; high ox. states are covalent.•MnCl2 solid contains Mn2+ and Cl- ions•MnO4- contains covalent Mn-O bondsCoordination ChemistryWhich transition metal has the electron configuration [Ar]3d3 in the +4 oxidation state?Which transition metal has the electron configuration [Kr]4d8 in the +2 oxidation state?Oxidation StatesTransition metal ion properties:•Ions with a partially filled d-subshell make good catalysts.Zn2+Pt2+Pt0Oxidation StatesBiological Catalysts:•Iron can exist as Fe2+ or Fe3+ and acts as an electron shuttleIron-sulfur