1. Do Now Welcome Back! HMSA: we have 1st lunch!
Take out Atoms/Nuclear packet from last week to get checked
Today: Energy, Waves
Next week: flame test lab 

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

3. 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)

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

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

6. MICROWAVES
Making popcorn

7. Using the remote control
INFRARED LIGHT
Using the remote control

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

9. ULTRAVIOLET LIGHT
Using a tanning booth

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

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

13. 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

15. 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

16. 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)

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

18. 3.17 m
1.70 x J
8.28 x J
1.0 x 10-5 m

19. Electrons and Energy Levels
Each electron has a distinct amount of energy that is related to the energy level (shell) it is in
Electrons with the lowest energy are found in the shell closest to the nucleus
Electrons with the highest energy are found in the shell furthest from the nucleus
The greater the distance from the nucleus, the greater the energy of the electron

20. Each energy level has a maximum number of electrons that it can hold
The smallest energy level (the one closest to the nucleus, the first) can hold 2 electrons.
The second energy level, can accommodate 8 electrons.
The third energy level, can accommodate 18 electrons.
The 4th energy level can accommodate 32 electrons
N e
1 2
2 8
3 18
4 32

21. HOW DOES A NEON SIGN WORK?
BECAUSE OF ELECTRONS

22. Ground vs. Excited State
Ground state=when the electrons occupy the lowest energy levels possible
Excited state=electrons are found in a higher energy level or shell (even when a lower energy levels is not completely full)

23. Ground and Excited State
When an electron gains energy, it jumps to a higher energy level or shell
This is a very unstable condition
We call this condition the excited state
Very rapidly, an electron in the excited state will lose energy and move back to a lower energy level or shell
When excited electrons fall from an excited state to a lower energy level, they release energy in the form of light

24. Ground  Excited State
Electron gains energy from heat, light, electricity
Electron “jumped” to a higher energy level (shell)

25. Excited  Ground State Electron releases energy in the form of light
Electron “falls” back and returns to ground state (normal position)

26. Ground and Excited State Summary
Ground State  Excited State
Energy is absorbed (gained)
Excited state is produced
Excited State  Ground State
Energy is released (in the form of light)
Ground state is produced

27. Bright Line Spectrum
Electrons falling from an excited state down to the ground state give off visible light
Different elements produce different colors of light or spectra
These spectra are unique for each element (just like a human fingerprint is unique to each person)

28. Demo