Chapter 8 Diamagnetic means that electrons are paired Core electrons n 1 inner electrons o Previous noble gas o D shell counts as core electrons ONLY if filled Outermost electron highest n value electrons o Ex Na ends with 3s1 so only 1 outermost electron o Ex P has 5 outermost electrons Valence electrons outermost electrons n 1 d shell electrons are used to form bonds o Relates to the periodic group ex group 1 has 1 group 2 has 2 group 7 has 7 o F block electrons are never valence EXCEPT for Ce all rare earths have 3 electrons Electron Configuration 1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 4f 5d 6p 7s 5f 6d 7p S block 1 orbital 2 electrons P block 3 orbitals 6 electrons D block 5 orbitals 10 electrons F block 7 orbitals 14 electrons When writing the electron configuration for ions remove outermost electrons first s shell Exceptions to electron configuration rule A Group 11 elements Cu Ag Au they take electron from the S shell and put it in D shell a Cu Ar 4s1 3d10 has 1 valence electron Cu1 B Eu Xe 6s2 4f7 takes an electron from d shell and puts it in f shell to pair all electrons has 2 valence electrons Eu2 Exceptions Cr Cu Ag Au Eu Real nuclear charge Z the of protons in the nucleus core electrons feel the real nuclear charge but valence electrons do not valence electrons are shielded Effective Nuclear Charge Zeff nuclear charge a valence electron actually feels o The greater the charge valence electrons feel the tighter they are pulled in size Size of atoms inversely related to Zeff the tighter electrons are pulled in the smaller the size harder to remove electrons when they are held together tighter Ionization Energy IE Energy required to remove an electron When elements goes from happy full shell to unhappy it requires a lot of energy Removing an electron from a full outer shell is when an atom requires more IE 10 fold 3 Factors effect IE 1 Electron configuration 2 Size of atom ion 3 Effective nuclear charge Electron Affinity EA energy released when electron is added Same trend as effective nuclear charge Electronegativity ability of an atom to attract an electron to itself in a chemical environment Electron Configuration Practice When writing the electron configuration for ions remove outermost electrons first s shell N z 7 1s2 2s2 2p3 3 unpaired electrons O z 8 1s2 2s2 2p4 2 unpaired electrons Ne z 10 1s2 2s2 2p6 0 unpaired electrons P z 15 Ne 3s2 3p3 3 unpaired electrons 5 outermost electrons K z 19 Ar 4s1 1 outermost electron Ca z 20 Ar 4s2 2 outermost electrons Ca2 only way we find it in nature Ar 4s0 Ca2 loses 2 electrons and therefore acts as Ar Sc z 21 Ar 4s2 3d1 2 outermost electrons 3 valence electrons Sc3 21 protons 18 electrons Ar Ti z 22 Ar 4s2 3d2 Ti II ion 22 20 Ar 4s0 3d2 we remove the outermost electrons first Ti IV ion 22 18 Ar 4s0 3d0 OR Ar As z 33 Ar 4s2 3d10 4p3 28 core electrons Ar 10 d shell 5 valence 5 outermost As 3 33 36 Kr Fe z 26 Ar 4s23d6 18 core electrons 2 outermost electrons 8 valence electrons Fe 3 iron III ion Ar 3d5 Took out the outermost electrons first S block than d block La z 57 Xe 6s2 5d1 3 valence electrons Ce z 58 Xe 6s2 5d1 4f1 4 valence electrons only F shell electrons in Ce can be valence Nd z 60 Xe 6s2 5d1 4f3 3 valence electrons F shell electrons do not count as valence Nd3 60 57 Xe 4f3 took outermost electrons first Gd z 64 Xe 6s2 5d1 4f7 3 valence electrons f shell electrons do not count Gd3 64 61 Xe 4f7 took outermost electrons first Hf z 72 Xe 6s2 4f14 5d2 68 core electrons 54 from Xe and 14 from f shell since its filled Pb z 82 Xe 6s2 4f14 5d10 6p2