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Inorganic Chemistry Duward Shriver and Peter Atkins Dr. S. M. Condren Dr. S. M. Condren Dr. S. M. Condren Dr. S. M. Condren CHEM422 Lab • Wednesday • Friday • Other Dr. S. M. Condren Dr. S. M. Condren Periodic Table Exam • Write chemical symbol for first 36 elements in proper location on blank periodic table • Worth 40 points total • Up to 36 for elements 1-36 • No more than 4 points for other elements • First attempt during week of Feb. 10. • Part of 400 total points for “Homework” Dr. S. M. Condren Chapter 1 Atomic Structure Dr. S. M. Condren Structure of the Atom Composed of: protons found in nucleus • protons relative charge of +1 relative mass of 1.0073 amu • neutrons neutrons • electrons found in nucleus neutral charge relative mass of 1.0087 amu electrons found in electron cloud relative charge of -1 relative mass of 0.00055 amu Dr. S. M. Condren Atomic Number, Mass Number, & Isotopes • Atomic number, Z Nuclear Notation – the number of protons in the nucleus – the number of electrons in a neutral atom A – the integer on the periodic table for each element E Z • Mass Number, A – integer representing the approximate mass of an atom – equal to the sum of the number of protons and neutrons in the nucleus • Isotopes – atoms of the same element which differ in the number of neutrons in the nucleus – designated by mass number Dr. S. M. Condren Isotopes vs. Allotropes Isotopes - atoms of the same element with different numbers of neutrons - different compounds with the same formula Allotropes - different forms of an element Carbon exhibits both • Isotopes: C-12 C-13 C-14 • Allotropes: graphite, diamond, and fullerenes Dr. S. M. Condren Big-Bang • starts with universe as a singularity with infinite density and temperature, only radiation exists • sudden expansion leads to rapid drop in temperature and density • nuclear particle transformations convert most of universe’s energy to protons and deuterons Dr. S. M. Condren The Origin of the Elements • Nucleosynthesis of light elements • Nucleosynthesis of heavy elements Dr. S. M. Condren Hydrogen Burning Hydrogen Burning (fusion) 4 1H ---> 4He + 2 positrons + 2 neutrinos + 2.5 x 106 MJ/mol after about 1/10 of hydrogen consumed, changes to helium burning Dr. S. M. Condren Helium Burning and Helium Reactions Helium Burning (fusion) 3 4He ----> 12C Helium Reactions 12C + 4He ---> 16O 16O + 4He ---> 20Ne 20Ne + 4He ---> 24Mg when temperature reaches 5 x 108 K, carbon fusion Dr. S. M. Condren Carbon Burning 2 12C ---> 23Na + 1H 2 12C ---> 20Ne + 4He etc. Dr. S. M. Condren Neutron Capture 68Zn + 1n ---> 80Br + 1n ---> 69Zn* ---> 81Br* ---> etc. Dr. S. M. Condren + b 81Kr + b 69Ga Average Binding Energy per Nucleon Dr. S. M. Condren Relative Penetrating Powers of Radiation Dr. S. M. Condren Decay Scheme for Uranium Series Dr. S. M. Condren Classification of the Elements Metals • Lustrous, malleable, ductile, electrically conducting solids at room temperature Nonmetals • Often gases, liquids, or solids that do not conduct electricity appreciably Metalloids • Elements, alloys or compounds that possess some of the characteristics of metals and some of nonmetals Dr. S. M. Condren Classification of the Elements • Metallic elements combine with nonmetallic elements to give compounds that are typically hard, non-volatile solids • When combined with each other, the nonmetals often form volatile molecular compounds • When metals combine (or simply mix together) they produce alloys that have most of the physical characteristics of metals Dr. S. M. Condren Development of Periodic Table Dmitri Mendeleev - Russian 1869 - Periodic Law - allowed him to predict properties of unknown elements Dr. S. M. Condren Missing elements: 44, 68, 72, & 100 amu Dr. S. M. Condren Dr. S. M. Condren C&EN COVER STORY: Dec. 20, 2004 Organometallic and Inorganic Chemistry A stable compound containing a silicon-silicon triple bond. Zinc-Zinc Bond Sekiguchi A, Kinjo R, Ichinohe M. Department of Chemistry, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan. [email protected] The reaction of 2,2,3,3-tetrabromo-1,1,4,4tetrakis[bis(trimethylsilyl)methyl]-1,4-diisopropyltetrasilane with four equivalents of potassium graphite (KC8) in tetrahydrofuran produces 1,1,4,4tetrakis[bis(trimethylsilyl)methyl]-1,4-diisopropyl-2tetrasilyne, a stable compound with a silicon-silicon triple bond, which can be isolated as emerald green crystals stable up to 100 degrees C in the absence of air. The SiSi triple-bond length (and its estimated standard deviation) is 2.0622(9) angstroms, which shows half the magnitude of the bond shortening of alkynes compared with that of alkenes. Unlike alkynes, the substituents at the SiSi group are not arranged in a linear fashion, but are trans-bent with a bond angle of 137.44(4) degrees. Dr. S. M. Condren Decamethyldizincocene, synthesized by Carmona and coworkers, is the first stable molecule with a bond between two zinc atoms (green). Hydrogens are not shown. Periodic Table of the Periodic Table of the Elements Elements IA 1 1 3 4 5 6 7 III B IV B VB VI B VII B VIII B IB II B III A IV A VA VI A VII A 1 VIII A 2 H H He 1.008 1.008 4.0026 10 3 2 II A 4 5 6 7 8 9 Li Be B C N O F Ne 6.939 9.0122 10.811 12.011 14.007 15.999 18.998 20.183 11 12 13 14 15 16 17 18 Na Mg Al Si P S Cl Ar 22.99 24.312 26.982 28.086 30.974 32.064 35.453 39.948 19 20 31 32 33 34 35 36 21 22 23 24 25 26 27 28 29 30 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se 39.102 40.08 44.956 47.89 50.942 51.996 54.938 55.847 58.932 58.71 63.54 65.37 69.72 72.59 74.922 78.96 Br 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe 85.468 87.62 88.906 91.224 92.906 95.94 * 98 101.07 102.91 106.42 107.9 112.41 114.82 118.71 121.75 127.61 126.9 131.29 55 56 57 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 79.909 Kr 83.8 Cs Ba **La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn 132.91 137.33 138.91 178.49 180.95 183.85 186.21 190.2 192.22 195.08 196.97 200.29 204.38 207.2 208.98 * 209 * 210 * 222 87 88 89 104 105 106 107 108 109 110 111 112 113 114 115 116 Rf Ha Sg Ns Hs Mt * 261 * 262 * 263 * 262 * 265 * 268 Fr * 223 Ra ***Ac 226.03 227.03 58 * Designates that **Lanthanum all isotopes are Series radioactive *** Actinium Series 59 60 61 62 Uun Uuu Uub * 269 * 272 63 64 * 277 65 Uut 118 Uuq Uup Uuh Uuo *284 *285 *288 *292 Based on symbols used by ACS 66 67 68 69 S.M.Condren 2007 *294 70 71 Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu 140.12 140.91 144.24 * 145 150.36 151.96 157.25 158.93 162.51 164.93 167.26 168.93 173.04 174.97 90 91 92 93 94 95 96 97 98 99 100 101 102 103 Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr 232.04 231.04 238.03 237.05 * 244 * 243 * 247 * 247 * 251 * 252 * 257 * 258 * 259 * 260 Dr. S. M. Condren Dr. S. M. Condren Quantum Mechanics: Wave Nature of Electrons Atomic Force Microscope Crommie, Lutz & Eigler http://www.almaden.ibm.com/vis/stm/corral.html Dr. S. M. Condren Dr. S. M. Condren Developed in collaboration with the Institute for Chemical Education and the Magnetic Microscopy Center University of Minnesota http://www.physics.umn.edu/groups/mmc/ Dr. S. M. Condren http://mrsec.wisc.edu/ http://mrsec.wisc.edu/ Sample http://www.nsf.gov/mps/dmr/mrsec.htm http://www.nsf.gov/mps/dmr/mrsec.htm Probe Pull Probe Strip Dr. S. M. Condren Pull Probe Strip Which best represents the poles? (a) (b) (c) North South Dr. S. M. Condren Quantum Numbers n => principal quantum number, quantized energy levels, which energy level n = 1, 2, 3, 4, 5, 6, 7, etc. Dr. S. M. Condren Quantum Numbers l => secondary quantum number, quantized orbital angular momentum, which sublevel or type of orbital s type orbital l = 0 p type orbital l = 1 d type orbital l = 2 f type orbital l = 3 g type orbital l = 4 Dr. S. M. Condren Quantum Numbers m => magnetic quantum number, quantized orientation of angular momentum, which orbital within sublevel s type orbital m=0 p type orbital m = +1, 0 or -1 one value for each of the three p orbitals d type orbital m = +2, +1, 0, -1 or -2 one value for each of the five d orbitals f type orbital m = +3, +2, +1, 0, -1, -2 or -3 one value for each of the seven f orbitals Dr. S. M. Condren Hydrogenic Energy Levels hcZ2R E = - ----------n2 where n = 1, 2, 3, hhh R = Rydberg constant mce4 R = ----------- = 13.6 eV 8h3ceo2 Dr. S. M. Condren s- and p-orbitals Dr. S. M. Condren d-orbitals Dr. S. M. Condren f-orbitals Dr. S. M. Condren Many Electron Atoms • Electronic Configuration • Pauli exclusion principle – No more than 2 electrons can occupy a single orbital – No two electrons can have the exact same four quantum numbers Dr. S. M. Condren Electron Filling Order Diagram Start here 1s 2s 3s 4s 5s 6s 7s 2p 3p 4p 5p 6p 7p 3d 4d 4f 5d 5f 6d Dr. S. M. Condren Ground state electronic configurations Dr. S. M. Condren Electronic Configuration As atom 33 electons 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d10, 4p3 or [Ar] 4s2, 3d10, 4p3 Dr. S. M. Condren Mn: [Ar]4s2 3d? How many d electrons does Mn have? 4, 5, 6 Dr. S. M. Condren Electronic Configuration negative ions add electron(s), 1 electron for each negative charge S-2 ion (16 + 2) electrons 1s2, 2s2, 2p6, 3s2, 3p6 Dr. S. M. Condren Electronic Configuration positive ions remove electron(s), 1 electron for each positive charge Electrons are first removed from orbital with highest n &l Mg+2 ion (12-2) electrons 1s2, 2s2, 2p6 Fe atom Fe+2 ion (26) electrons (26-2) electrons [Ar]4s23d6 [Ar]4s03d6 Dr. S. M. Condren How many valence electrons are in Cl, [Ne]3s2 3p5? 2, 5, 7 Dr. S. M. Condren Shielding Z* => effective nuclear charge Z* = Z - S S => shielding as defined by Slater’s Rules http://en.wikipedia.org/wiki/Slater's_rules Dr. S. M. Condren Slater's Rules for Calculating Shielding 1. for [ns, np] electrons (e-s), e-s to the right in the modified electronic configuration contribute nothing 2. for [ns, np] e-s, other electrons of same group contribute 0.35 each (except 1s, 0.3) 3. each electron in n - 1 group, contribute 0.85 4. each electron in n - 2 group, contribute 1.0 5. nd & nf group, rules 1 & 2 remain the same, all electrons to the left contribute 1.0 modified electronic configuration [1s][2s2p][3s3p][3d][4s] etc Dr. S. M. Condren Examples: for the 4 s electron in Cu atom [1s2][2s22p6][3s23p6][3d10][4s1] n - 2 group => 10 * 1.0 n - 1 group => 18 * 0.85 n group => 0 * 0.35 Z* = 29 - ((10 * 1.0) + (18 * 0.85) + (0 * 0.35)) = 29 - 10 - 15.3 = 3.7 Dr. S. M. Condren Example: for a 3 d electron in Cu atom [1s2][2s22p6][3s23p6][3d10][4s1] rule 5. group 18 * 1.0 9 other d electrons * 0.35 Z* = 29 - ((18 * 1.0) + (9 * 0.35)) = 29 - 18 - 3.2 = 7.8 Dr. S. M. Condren Effective Nuclear Charge Name Z hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine neon sodium magnesium aluminum silicon phosphorus sulfur chlorine argon potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium Effective Nuclear Charge n-2 n-1 n 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 Z* 1 2 2 2 2 2 2 2 2 10 10 10 10 10 10 10 10 10 10 10 10 10 10 Dr. S. M. Condren 2 2 2 2 2 2 2 2 8 8 8 8 8 8 8 8 8 8 9 10 11 13 13 14 15 16 18 18 18 18 1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 1 1 1 1 1 1 1 1 2 3 1 1.7 1.3 1.95 2.6 3.25 3.9 4.55 5.2 5.85 2.2 2.85 3.5 4.15 4.8 5.45 6.1 6.75 2.2 2.85 3 3.15 3.3 2.95 3.6 3.75 3.9 4.05 3.7 4.35 5 5.65 Effective Nuclear Charge vs. Atomic Number 9 8 Effective Nuclear Charge 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Atomic Number Dr. S. M. Condren Atomic Radius • decrease left to right across a period – as nuclear charge increases, number of electrons increase; however, the nucleus acts as a unit charge while the electrons act independently, pulling electrons towards the nucleus, decreasing size • increase top to bottom down a group – each additional electron “shell” shields the outer electrons from the nuclear charge • increases from upper right corner to the lower left corner Dr. S. M. Condren Elemental Properties vs. Atomic Number 9 8 7 6 5 Z* 4 a. radius 3 2 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Atomic Number Dr. S. M. Condren Ionic Radius • same trends as for atomic radius • positive ions smaller than atom • negative ions larger than atom Isoelectronic Series • series of negative ions, noble gas atom, and positive ions with the same electronic confiuration • size decreases as “positive charge” of the nucleus increases Dr. S. M. Condren Ionization Energy • energy necessary to remove an electron to form a positive ion, I • low value for metals, electrons easily removed • high value for non-metals, electrons difficult to remove • increases from lower left corner of periodic table to the upper right corner Dr. S. M. Condren Ionization Energies first ionization energy • energy to remove first electron from an atom second ionization energy • energy to remove second electron from a +1 ion etc. Dr. S. M. Condren Elemental Properties vs. Atomic Number 30 25 20 Z* 15 1st I. E. 10 5 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 Atomic Number Dr. S. M. Condren Electron Affinity • energy released when an electron is added to an atom • same trends as ionization energy, increases from lower left corner to the upper right corner • metals have low “Ea” • nonmetals have high “Ea” Dr. S. M. Condren Elemental Properties vs. Atomic Number 30 25 20 15 Z* 1st I. E. E.A. 10 5 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 -5 Atomic Number Dr. S. M. Condren Electronegativity Pauling Scale • relative attraction of an atom for electrons, its own and those of other atoms • same trends as ionization energy, increases from lower left corner to the upper right corner • fluorine: E.N. = XP = 4.0 • based on the energetics of bond formation Dr. S. M. Condren Electronegativity Milliken Scale • Based on the average of the ionization energy and electron affinity • XM = ½(I + Ea) Dr. S. M. Condren Elemental Properties vs. Atomic Number 30 25 20 15 Z* 1st I. E. E.A. EN. 10 5 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 -5 Atomic Number Dr. S. M. Condren