1. Welcome Back! Please hand in independent study packet up front
If your facebook project is not on the google doc, hand it in/ it to me/share it with me
I am EXTREMELY jet-lagged, so forgive me if I seem unfocused today…

2. Review: Bohr Model of the Atom
Electrons are shown in concentric shells or energy levels around the nucleus
The 1st shell can hold up to 2 electrons
The 2nd shell can hold up to 8 electrons
The 3rd shell can hold up to 18 electrons
The 4th shell can hold up to 32 electrons
When filling electrons, you fill the first (inner) shell first

3. Electrons
Valence electrons= electrons in the outermost shell of the atom

4. Lewis Structures (Electron Dot Diagrams)
A Lewis structure is in a sense a shortcut for representing the structure of an atom.
A Lewis structure contains 2 parts
1. element symbol (representing the nucleus)
2. electron dots (representing the valence electrons)

5. Lewis Structure Example
N has 5 valence electrons, so it’s Lewis structure would look like:
Maximum 2 electrons per side!
Note: by convention, you should not have more than 2 electrons per “side”
The maximum number of valence electrons you can have is 8.

6. Practice and Review
Use the example to help you fill out the Bohr Diagrams, Electron Configuration, and Valence Electrons

7. What do these 6 items all have in common?

8. Electromagnetic radiation
- a form of energy that has wavelike properties
- all forms found in the electromagnetic spectrum
Examples of electromagnetic radiation:
Xrays
Microwaves
Light waves
Radio waves – when you hear static on the radio when you aren’t getting a signal, that is the leftover microwaves from the big bang 15 billion years ago (it is cooling off so now the waves are the energy and wavelength of radio waves)

9. ELECTROMAGNETIC RADIATION
RADIO
WAVES
MICRO-
WAVES
INFRARED
LIGHT
VISIBLE
LIGHT UV
LIGHT
X-RAYS
LOWEST
ENERGY
HIGHEST
ENERGY

10. Listening to music in the car using the radio
RADIO WAVES
Listening to music in the car using the radio

11. MICROWAVES
Making popcorn

12. Using the remote control
INFRARED LIGHT
Using the remote control

13. The blue color of the sky
VISIBLE LIGHT
The blue color of the sky

14. ULTRAVIOLET LIGHT
Using a tanning booth

15. X-RAYS
Checking to see if the
ankle was broken

17. Examples of Waves All EMR waves move following a specific pattern, but the energies and characteristics associated with the waves can vary

18. Determining Characteristics of a Wave
Use string to make waves
Try your best to estimate the measurements
Assume the length of 1 tile is 1 foot

19. Homework

20. Photons - released during electromagnetic radiation
– tiny particles that have no resting mass which carry a quantum of energy
All photons travel at the speed of light in a vacuum

21. Photons behave as particles
quantum – the minimum amount of energy that can be absorbed or released from an atom
- cannot be any value but are in discrete energy levels (like bundles or packets of energy)
quantized = certain energy levels, not all can be reached (like monkey bars, you can’t grab a bar that is in between, it’s not possible)

22. 𝑐=𝑣λ
3.00× 10 8 =𝑣×4.9× 10 −7
𝒗=𝟔.𝟏× 𝟏𝟎 𝟏𝟒 𝑯𝒛

23. 3.17 m
1.70 x J
8.28 x J
1.0 x 10-5 m