1. Before Bell Rings Grab Packet From Side Table .

2. ETD
Draw + Explain Rutherford’s Experiment + What this told us about the atom.
What would have happened if Thomson was correct?

3. ETD 2 ANSA+B
Draw + Explain Rutherford’s Experiment + His 4 Big Ideas.
What would have happened if Thomson was correct?
Rutherford knew there must be a nucleus because the positive charge in the atom was concentrated, otherwise the alpha particles would not have been deflected.
He knew it was positive because they deflected the positively charged alpha particles and he knew it was small because most of the particles went straight through.
He knew it was mostly empty space because most of the particles went straight through.
He knew electrons must be outside the nucleus because if they were inside, the overall charge for the nucleus would be neutral and would not deflect the alpha particles.
If Thompson’s Plum Pudding Model was correct, all of the alpha particles would have gone straight through, since there would not have been a concentrated positive charge that would make them deflect.

4. Rutherford Experiment
Another visual of the experiment. You can see the alpha particles being deflected as they interact with the nuclei in the gold foil.

5. Microscopic
Rutherford wanted to have the foil as thin as possible so he could identify what was causing they deflection. If it was a block of gold, most of the alpha particles would have been deflected and it would be harder to draw conclusions about the size and charge of the nucleus.

6. Why weren’t the electrons being “pulled” into the nucleus?
Big Problem?
Why weren’t the electrons being “pulled” into the nucleus?
The problem with Rutherford’s model was that, since electrons and protons are attracted to each other, why wouldn’t they just come together in the nucleus and cancel out?

7. What a Bohr…

8. Bohr
Looks at Light

9. White Light

10. White light is made up of all the colors of the spectrum combined.

11. Continuous vs Line Spectra
A continuous spectra shows all the colors of the rainbow, but when different elements are excited, the only give line spectra, seen as mostly black spectra with a few lines color in them.

12. H N
These spectra a different for each element and tell us about how the electrons in the element are moving. Light is released as a an electron moves from an excited state (an energy level farther from the nucleus) to an energy level closer to the nucleus. Since an electron has less energy closer to the nucleus, that energy has to go somewhere, so it is emitted as a photon (visible light). Ar

13. POGILs Process Orientated Guided Inquiry Learning 3 Roles
Facilitator Keeps group moving A/D
Spokesperson Raises hand, answers ?s B/E
Reader Reads aloud C/F
STOP at Stop Signs so I can ask some questions

14. Homework Finish Electron Energy and Light POGIL Finish Super Models WS
Due next class