1. ELECTRONIC STRUCTURE AND THE PERIODIC LAW Dr Sharipah Ruzaina Syed Aris srsa_july2009

7. Illustrating Orbital Occupancies The electron configuration n l # of electrons in the sublevel The orbital diagram (box or circle) Order for filling energy sublevels with electrons srsa_july2009 as s,p,d,f

8. dark - filled, spin-paired light - half-filled no color-empty A vertical orbital diagram for the Li ground state srsa_july2009

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10. Condensed ground-state electron configurations in the first three periods. srsa_july2009

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13. A periodic table of partial ground-state electron configurations srsa_july2009

14. PERIODIC TRENDS IN ATOMIC PROPERTIES *size *Ionization energy *electron affinity srsa_july2009

18. Periodicity of first ionization energy (IE 1 ) srsa_july2009

19. Variations in first ionization-energies. Elements with the largest ionization energies are in the upper right of the periodic table. Those with the smallest ionization energy are at the lower left. srsa_july2009

20. Ranking Elements by First Ionization Energy PLAN: SOLUTION: (a) Kr, He, Ar (b) Sb, Te, Sn (c) K, Ca, Rb (d) I, Xe, Cs IE decreases as you proceed down in a group; IE increases as you go across a period. Group 8A(18) - IE decreases down a group. Period 5 elements - IE increases across a period. Ca is to the right of K; Rb is below K. I is to the left of Xe; Cs is furtther to the left and down one period. srsa_july2009 PROBLEM: Using the periodic table only, rank the elements in each of the following sets in order of decreasing IE 1 : (a) He > Ar > Kr (b) Te > Sb > Sn (c) Ca > K > Rb (d) Xe > I > Cs

22. Electron affinities of the main-group elements. srsa_july2009

24. Trends in three atomic properties. srsa_july2009