2. What is the periodic table? compact way of organizing elements contains a lot of information allows us to make predictions about behavior and properties of elements based on their positions in PT Element Song

4. History of the Periodic Table end of 1700’s – less than 30 elements known many elements discovered during 1800’s many experiments done to determine atomic masses of the new elements

6. John Newlands 1864: if arrange elements by atomic mass – properties: repeat every 8 th element Law of Octaves –did not work for all known elements Key Idea was correct: properties of elements do repeat in periodic manner

7. Mendeleev & Meyer 1869: Mendeleev produced 1 st accepted PT – elements: in columns according to ↑ atomic mass – elements with similar properties grouped together predictedpredicted existence & properties of undiscovered elements not totally correct –more accurate atomic mass calculations showed some elements were not in right place

9. Remember 1860’s: Dalton’s billiard ball model of the atom NO subatomic particles yet discovered

10. 1913 – Henry Moseley by 1913, protons & electrons discovered –neutrons were predicted Moseley determined atoms of each element contain unique # protons (= atomic number) re-arranged Mendeleev’s PT according to atomic number instead of atomic mass problems with elements in wrong place disappeared

11. Periodic Law increasing atomic number There is a periodic repetition of the elements chemical and physical properties if they are arranged by increasing atomic number

12. Glenn Seaborg: 1950’s Lanthanide and Actinide Series

15. Seaborg Mendeleev Mosley Newlands

17. Classifying the Elements metals2/3 (75%) of elements are metals non-metals metalloidsremaining elements: non-metals & metalloids (semi-metals) metalloids: –have properties of both metals & non-metals staircase:staircase: –dividing line between metals & non-metals –elements to left are metals (except H) –elements to right are non-metals

18. Vocabulary of PT groupsfamiliescolumns called groups or families –today: #1 thru 18, Arabic numerals –past: A & B groups, Roman numerals A-Group (tall columns) –columns 1,2,13-18 (= representative elements) –IA – 8A B-Group (short columns) –transition metals (columns 3-12) –IB - 8B seriesperiodsrows are called series or periods –#1 thru 7

19. Column numbering (1  18) left to right Period numbering (1  7) top to bottom

20. Names of Families AKA: A group elements Group 1 = Alkali Metals Group 2 = Alkaline Earth Metals Group 13 = Boron family Group 14 = Carbon family Group 15 = Nitrogen family Group 16 = Oxygen family Group 17 = Halogens Group 18 = Noble Gases AKA B group elements Groups 3-12: Transition metals

21. Transition Metals Groups 3 through 12 AKA group B elements Actinide & Lanthanide series –inner transition elements put the COLOR in your life –form brightly colored salts/solutions

22. Elements that are gases at STP Diatomics: H 2, N 2, O 2, F 2, Cl 2 Monatomics: noble gases He, Ne, Ar, Kr, Xe, Rn

23. Two elements are liquid at room temperature Br 2 (non-metal) and Hg (metal)

24. All other elements are solids at room temperature

25. Structure of Periodic Table closely related to electron configuration of each element

26. Energy Levels = Row Number elements in same row have same # of principal energy levels –so # of principal energy levels = to row #

27. Going Across Row 2: 2-8Ne18 (VIIIA) 2-7F17 (VIIA) 2-6O16 (VIA) 2-5N15 (VA) 2-4C14 (IVA) 2-3B13 (IIIA) 2-2Be2 (IIA) 2-1Li1 (IA) ConfigurationElementFamily

28. Valence Electrons chemical behavior determined by # valence electrons elements with same # valence electrons will have similar chemical properties –elements in same column have similar chemical properties

29. Going Down Column 1: 2-8-18-32-18-8-1Fr7 2-8-18-18-8-1Cs6 2-8-18-8-1Rb5 2-8-8-1K4 2-8-1Na3 2-1Li2 1H1 ConfigurationElementPeriod

30. Valence Electrons 414 or IVA 313 or IIIA 22 or IIA 11 or IA Number of Valence Electrons Group

31. PROPERTIES of the Elements

32. Properties of Metals malleable – flattened into sheets ductile – drawn into wires & tubes have Luster good conductors of heat & electricity solid at room temperature (except Hg) “Metals are losers”metals lose electrons & form positive ions “Metals are losers” low ionization energy low electronegativity

33. Properties of Non-metals generally gases or solids (except Br 2 ) solids are brittle solids are dull poor conductors of heat & electricity non-metals gain electrons & form negative ions “Non-metals are winners” “Non-metals are winners” high ionization energy high electronegativity

34. Properties of Metalloids 7 metalloids: –5 on right of staircase: B,Si,As,Te,At –2 on left of staircase: Ge,Sb Each metalloid has some metallic and some non- metallic properties example: Si shiny like metal but brittle like non-metal