Chapter 6 & 7 Electronic Nature of Atoms & Periodic Trends

For an excellent tutorial in this section please go to

http://www.wwnorton.com/chemistry/tutorials/ch3.htm

1. The student will recognize and define wavelength, amplitude and frequency for any given wave.
2. Recognizing that n is the frequency (in Hz or 1/sec), l is the wavelength (in nm) and c is the speed of light (3.00 x 10⁸ m/s), then    nl = c.
3. Energy of a wave is E=hn.   Since n=c/l then E=hc/l Planck’s constant,

h = 6.63 x 10^-34 Js.

4. Radiant energy behaves as a particle; these energy packets are called photons.
5. Know that a spectrum is radiation separated into its different wavelengths.  There are continuous and line spectrum. 
6. Balmer’s spectrum of hydrogen follows the equation n=C(1/2²-1/n²)  C is the constant 3.29 x 10¹⁵s^-1  (see Balmer info on 3 out of 16 of your AP study cards)
7. Bohr stated that the electrons are in permitted orbits, each orbital has a specific energy state.  Such that: En = (-R_H)(1/n²) n=1,2,3,4…    R_H =2.18x 10^-18J
8. When an electron moves from a lower state to a higher state, it absorbs energy.  When an electron moves from a higher state to a lower state, it releases energy, often in the form of light.
9. Louis de Broglie and the wavelength of a particle l=h/mn.
10. But where is the electron?  The uncertainty principle does not tell you, it only tells you the probability of where it is.  The electron does not move in a circular orbit, but moves around the nucleus in a pattern that more closely resembles a cloud.
11. Quantum numbers: 

·         n=the principle quantum number.  n=1,2,3…  as n increases, the orbital becomes larger and energy state is higher.

·         l= the shape of the orbital.  l=(n-1)  such that l=0,1,2…  and is designated by the letters s,p,d,f

·         m= the orientation in space m=(l and –l)

·         s=is the spin and equals either ½ or – ½

12. The orbital shapes: 

1s         2s                     p                      d

13. Pauli Exclusion principle:  no two electrons in an atom may have a the same set of quantum numbers
14. Aufbau principle:  electrons occupy the lowest energy level available.
15. Hund’s rule: place one electron in each orbital of an energy level before doubling them up.
16. The Rules:

17.

Additional Information:

Atomic Spectra for the spectra of neon                                                Why do Wintergreen Lifesavers make blue sparks?

Standing Waves a video, you need Windows Media player to view.

Atomic Radius & Periodic Table

Electromagnetic Spectra

Those Annoying Nodes

Recent (relatively) Discoveries and the Periodic Table

Worksheets

Atomic Structure part I                        Chapter 6&7 Study questions        Quantum numbers worksheet

Atomic Structure part II                        Chapter 6&7 practice test            Electron configuration worksheet

Bohr's Problems                                    Chapter 6 & 7 worksheet

LECTURES

Chapter 6 part I                                                    Chapter 7  part I

Chapter 6 part II                                                   Chapter 7 part II

Chapter 6 part III                                                

Chapter 6 review

Also:  A review of the development of the periodic from Chem. I