2. The Periodic chart and Its Patterns may seem like a mystery…

5. CASE OF THE PERIODIC TRENDS!

6. Investigate the size of certain atoms… You find a small scroll of paper… pm= picometer 10 -12: it’s a trillionth of a meter!

7. What causes the sizes of the atoms to change…

8. Within a family? Na K Why?Because K has More energy levels! 3 levels 4 Levels K will be Bigger!

9. What causes the sizes of the atoms to change… Within a period? Cl P Why? This time, they both have 3 Energy levels However, Chlorine has more protons in nucleus, making its nuclear (inward) pull greater… So the Cl atom is smaller!

10. YOU RECEIVE A NOTE FROM AN ANONYMOUS SOURCE…

11. Major Clues! Dear gang..hopes this helps! 1) More energy levels means bigger atoms/ions! 2)Increase in atomic numbers (protons) means more inward pull (+) toward the nucleus! 3) Loss of an energy level means it’s now smaller! 4) Electrons (-) farther out are shielded from the (+) pull of the nucleus by inner energy levels. Covertly, Mr. E. S.

12. On the back of the note…. There’s a small picture!

13. You study the size of atoms compared to their ions… It seems to show the size of ions…

14. What causes the sizes of the stable ions to change… Within a family? Within a period?

15. Mg Mg +2 Al Al +3 P P -3 Cl Cl -1 Why? Ca +2 Ca Why? ? Predict the size of the Cl -1 ion!

16. Hey gang, You need to know these words to proceed any further! I’ve used disappearing ink… Mr. E. S. 1 st ionization Energy- how much energy is needed to pull a valence e- off.

17. Shielding

18. 2nd 3rd 4th 1st nucleus Electrons are pulled inward by the positively charged nucleus Consider any electron in the second energy level… Note that the 1 st energy level is between these electrons and the nucleus The electrons creating the inner negative clouds “shield” these outer electrons from the positive nuclear pull. electron Nucleus (with + protons) 1 st energy level (shielding nucleus) Electron in 2 nd energy level Recap:

19. By definition, the first ionization energy of an element is the energy needed to remove the outermost, or highest energy, electron from a neutral atom in the gas phase.

20. What causes the change in the 1 st ionization energy… Within a period? O F Ne 1313.91681.02080.6 Why? how much energy is needed to pull valence e- off Which has more nuclear pull? Why? 89 10 More protons!

21. What causes the change in the 1 st ionization energy… Within a Family? Cl F 1139.9 1251.1 1681.0 Br Why? F has the Least shielding Valence e- held tightly It would take a lot of e- to steal from it

22. How Nuclear Pull affects… Size- The stronger the pull, the more closely it pulls the electrons inward making it SMALLER! 1 st Ionization energy- the stronger the pull, the more energy needed to pull off valence electron.

23. Excellent Job Gang!!! THE END ?

24. Bell Work: Date: Which will have the lower 1 st ionization Energy? Al or P? Cl or Br?

25. Which will have the higher 1 st ionization Energy? N or P? S or Cl? Which will have the lower 1 st ionization energy? P or As? Rb or Sr? Which will have the Higher 1 st ionization energy? F or O? Na or K? Bellwork: date: