2. Dobereiner’s Triads 7 + 39 = 23 2 For Li, Na and K

3. deChantcourtois’ Spirals

4. Newlands’ Octaves

5. Mendeleev (1869)

6. Lothar Meyer

7. Mendeleev’s Gaps

8. Henry Moseley Organized according to atomic number rather than atomic mass

9. Periodic Table

10. Periodic Table

11. Periodic Table Families

12. Alkali Metals 3 electrons 11 electrons 19 electrons 37 electrons 55 electrons 87 electrons

13. Alkali Metals 1s 2 2s 1 1s 2 2s 2 2p 6 3s 1 1s 2 2s 2 2p 6 3s 2 3p 6 4s 1 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 1 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 1 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 5d 10 5 6 p 6 7s 1

14. Alkaline Earth Elements 1s 2 2s 2 1s 2 2s 2 2p 6 3s 2 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 5d 10 5 6 p 6 7s 2

15. Noble Gases 1s 2 1s 2 2s 2 2p 6 1s 2 2s 2 2p 6 3s 2 3p6 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6

17. Halogens

18. Chalcogens

19. Blocks S block - Filling available s orbitals P block - Filling available p orbitals D block – Filling 3d, 4d, 5d and 6d orbitals F block – filling 4f and 5f orbitals

21. Atomic Size

23. Shielding Effect

24. Trends in Ionization Energy Low Energy = Easier to remove electron High Energy = Difficult to remove electron

25. Periodic Size Changes

26. Electronegativity

27. Electronegativity Trend

29. Ion Sizes

30. Ion Sizes

31. Periodic Trends

32. Boiling Point

33. Boiling Point Trends

35. Rare earth elements

36. Alchemy

39. Synthetic Elements

40. Lawrence’s Cyclotron

42. Island of Stability