1. Put this drill in your notebook!
Think back to physical science and earth science… what do you remember about waves?
Put this drill in your notebook!

2. Parts of a Wave
Wavelength (lambda = λ) - the shortest distance between equivalent points (crest to crest or trough to trough); can be in m, cm, or nm (1 x 10 -9)
Frequency (nu = ν) - the number of waves that pass a given point per sec. 1 hertz = 1 wave/sec or 1/s or s-1
Amplitude - wave’s height from the origin to a crest or a trough.

3. SWBAT: Define the terms frequency, wavelength, and amplitude.
Explain the relationship between wavelength and frequency.
List the major regions of the electromagnetic spectrum

4. Agenda 11/13 & 11/14/12 Review parts of a wave
Review how light energy is related to color
Electromagnetic spectrum
Review for Unit 4 Quest

5. SWBAT: Define the terms frequency, wavelength, and amplitude.
Explain the relationship between wavelength and frequency.
List the major regions of the electromagnetic spectrum

6. Homework Due Next Class:
Homework Check:
Valence Electrons
4-4 and 4-5 Practice Problems
Scavenger Hunt
Homework Due Next Class:
Unit 4 Test Review

7. Announcement
Unit 4 Test – Thursday/Friday
All MC questions

8. Unit 4 Quest Topics     1.  An atom's principal energy levels, sublevels, and orbitals     2.  Writing electron configurations (both unabbreviated and Nobel gas notation) using: Pauli exclusion principle, Aufbau principle and Hund's rule     3.  Valence electrons and unpaired electrons     4.  Wave and particle nature of light     5.  How light is related to an energy change of matter (ground state vs excited state of an electron)     6.  Continuous electromagnetic spectra (radio waves to gamma waves) vs atomic (element) emission spectra     7.  Parts of a wave and relationship between wavelength and frequency     8.  Speed of light (c) = wavelength x frequency (v)     

9. Dual Nature of Light
Wave: When the corresponding light is passed through a prism or spectrograph it is separated spatially according to wavelength, as illustrated in the following image.
Particle: Atoms can absorb and emit packets of electromagnetic radiation having discrete energies dictated by the detailed atomic structure of the atoms.

10. The Wave Description of Light
Visible light is a kind of electromagnetic radiation which is a form of energy that exhibits wavelike behavior as it travels through space.

11. Electromagnetic Radiation
Includes visible light, microwaves, X-rays, etc. Together all the different forms make up the electromagnetic (EM) spectrum. All forms of EM radiation travel at a speed of 3.00 x 108 m/s in a vacuum. This is the speed of light or c.

12. Electromagnetic Spectrum
R O Y G B I V
Visible light
Radio Micro IR UV X-rays Gamma
(m)

14. Electromagnetic Radiation is energy in Waves
The length of the wave is inversely related to its frequency
c = λν
Speed of light = wavelength × frequency
(m/s) (m) (1/s)
Speed of light = 3.00 × 108 m/s
Frequency is a measure of waves/second and has the units of 1/s or Hertz (Hz), the SI Unit.

15. We can use c = λν to calculate the wavelength or frequency of any wave
What is the wavelength of a microwave that has a frequency of 3.44 x 10 9 Hz?
c = λν; we need to solve for λ
λ = c/v
λ = 3.00 x 108 m/s λ = 8.72 x 10-2m
3.44 x 109 s-1

16. The Particle Description of Light
When certain frequencies of light strike a metal, electron are emitted.

17. Energy States of an Atom
The lowest energy state of an atom is its ground state (electron configuration).
When the potential energy of an atom increases, it changes to an excited state.

18. Energy States of an Atom
Electrons in an atom become excited by absorbing energy from the surroundings and jumping to new higher energy levels.
The excited state is less stable therefore the electron falls back or returns to the lower energy ground state.

19. Return to Ground State
When electrons fall back a wave with a specific amount of energy
is emitted – called a photon. If we see color then the emission is in the visible range
We perceive this as unique colors associated with particular elements

20. Relationship Between Energy & Color
When white light is passed through a prism a continuous spectrum (rainbow effect) is obtained.
Individual elements emit a spectrum containing discrete lines called a line spectrum

21. Summary Notes
When electrons absorb energy, they jump from lower to higher energy levels
Eventually, these electrons fall back to the ground level; when this happens, they emit energy of a particular wavelength
It is the frequency of that particular wavelength that our eyes interpret as color

22. Drill – 11/7/11 – QTR - #2
1. Determine the # of valence electrons for the following atoms: F P Ca 2. List from shortest to longest wavelength, radiation of the electromagnetic (EM) spectrum.

23. Drill – 11/7/11
1. Determine the # of valence electrons for the following atoms:
F - 7
P - 5
Ca - 2
2. List from shortest to longest wavelength, radiation of the electromagnetic (EM) spectrum.
Gamma, x-rays, UV, visible light, IR, Microwave, radio
Visible light = VIBGYOR

24. Homework – due Wed, 11/2/11 Complete Radiant Energy Worksheet
Complete Flame Test Lab (if not completed during class on Tues)

25. Important Message Flame Test Lab on Tuesday
Long hair should be tied back
No loose clothing items (sleeves, etc.)
No open-toed shoes

26. Drill #2 Nov. 9 & 12, 2012
Write the unabbreviated electron configuration for phosphorus (P).
Identify the number of unpaired electrons in an atom of phosphorus

27. Answers
1s22s22p63s23p3
It has 3 unpaired electrons

28. Trick for Remembering which sublevel comes next
The Diagonal Rule
Trick for Remembering how many orbitals are in each sublevel
s p d f

29. Homework Due next class:
Homework Check:
Electron Configuration Level 1 and 2
Homework Due next class:
Valence Electrons
4-4 and 4-5 Practice Problems
Scavenger Hunt

30. Valence Electrons
Valence electrons = # of e- in outermost orbital (highest principal en level)