1. Chapter 5: Electrons in Atoms

2. 3 major subatomic particles? ProtonElectronNeutron What is the charge on each? Which identifies the atom? Which tells the chemical properties?

4. structure of the atom? 1) Small, dense nucleus. 2) Nucleus is neutrons & protons. 3) Nucleus has a positive charge. 4) 4) Most mass is found in the nucleus 5) Electrons surround the nucleus and occupy most of the volume

5. Evolution of 3 Atomic Models 1. 1. John Dalton (1766 – 1844) : atomic theory 2. 2. J.J. Thomson (1856 – 1940) : electron 3. Ernest Rutherford (1871 – 1937) : nucleus Aren’t they cute!! didn’t tell of electron. didn’t tell locations & energy of electron. - + - - + - - + - + - + + - + - + - - + -

6. Bohr Planetary Model 1913 - 1913 - electrons orbit the nucleus Bohr asked “What prevents the electrons from falling into the nucleus?” w/ fixed amount of energy, fixed path & won’t fall inward

7. Niels Bohr (1885 – 1962) electrons exist in energy levels around nucleus Young Bohr Old Bohr Wild Bohr A Real Bore

8. Bohr - Bohr - electrons circles the nucleus & can “jump” levels Quantum – Minimum energy req. for electron to move levels

9. energy levels like steps.... not equally spaced. higher the step, more energy & farther away Energy Levels Sixth  Fifth  Forth  Third  Second  First  Nucleus 

10. A. All solid objects will change color when they are heated because they emit ________. Radiation - which is light The color that is produced by the emitted radiation depends on the _____ of the object. Temperature Example: Red glow from an electric stove

11. Bohr’s Model of the Atom

12. Erwin Schrodinger (1887 – 1961) Quantum Mechanical Model mathematical model - predicts location and energy Electrons don’t have definite energy level paths.

13. 90% probability region denser the cloud, greater probability

14. Schrödinger’s Famous Paradoxical Cat 1)cat in box, w/ a radioactive atom. 2)If atom decays, hammer hits flask w/ prussic acid 3)killing cat. Is the cat alive or dead? quantum mechanics, says: ” it wavers 50% dead 50%

15. e- exists in all locations, 1 location & sometimes no location

17. Electrons can’t exist between levels & change Levels electrons by gaining/losing an exact quantity of energy (1 quantum)

18. ELECTRONS IN SUB-ENERGY LEVELS WB P. 180 floor no. subLevel room bedS

19. S P D F

20. Electronic Configurations Aufbau Principle Aufbau Principle

21. Electronic Configurations use your periodic chart – page 1 use your periodic chart – page 1

23. Electronic Configurations 1 st row 1 st row

24. Electronic Configurations 1 st row 1 st row

25. Electronic Configurations 2 nd row 2 nd row

26. Electronic Configurations 2 nd row 2 nd row

27. Electronic Configurations 2 nd row 2 nd row

28. Electronic Configurations 2 nd row 2 nd row

29. Electronic Configurations 2 nd row 2 nd row

30. Electronic Configurations 2 nd row 2 nd row

31. Electronic Configurations 2 nd row 2 nd row

32. Electronic Configurations 2 nd row 2 nd row

33. Electronic Configurations 2 nd row 2 nd row

34. Electronic Configurations 3 rd row 3 rd row

35. Electronic Configurations 3 rd row 3 rd row

36. Electronic Configurations 3 rd row 3 rd row

37. Electronic Configurations 3 rd row 3 rd row

38. Electronic Configurations 3 rd row 3 rd row

39. Electronic Configurations 3 rd row 3 rd row

40. Electronic Configurations 4 th row 4 th row

41. Z= 2  What’s wrong with this?