Unit 4 Test: Quantum Physics

Today periods 1, 3 and 5 are taking the Unit 4 Test. The periods are 90 minutes long, so bring something to do for when you finish the test. I have lots of free books to read as well.

Unit 4 Review: Quantum Physics

Monday and Tuesday this week we are doing review problems for the unit 4 test, which will be on Wednesday, October 28 for periods 1, 3, and 5 and on Thursday, October 28 for periods 2 and 6. Periods 1, 3, and 5 will be 90 minutes long (see here), so when we're done with the test we'll go outside and hang in the sun (if there is sun) or play the Five Letter Word Game. If that doesn't appeal to you, bring something to do.

Here are the review questions (numbers taken from the blue Hewitt book):
2. What is a quantum? Give two examples.
3. What is a quantum of light called?
4. What is Planck's Constant, and how does it relate to the frequency and energy of a photon?
5. Which has more energy per photon - red light or blue light? Why?
6. What is the photoelectric effect?
11. As the speed of a particle increases, does its associated wavelength increase or decrease?
13. How does the energy of a photon compare with the difference in energy levels of the atom from which it is emitted?
20. Can the speeds and positions of electrons in an atom be measured with certainty?
21. What does it mean to say that a certain quantity is quantized?
23. A very bright source of red light has much more total energy than a dim source of blue light, but the red light does not eject electrons from a certain photosensitive surface. Why is this so?
24. Which photon has the most energy - one from infrared, visible, or ultraviolet light?
25. If a beam of red light and a beam of green light have exactly the same total amount of energy, which beam has the greater number of photons? Explain.
28. We do not notice the wavelength of moving matter in our ordinary experience. Is this because the wavelength is extraordinarily large or extraordinarily small?
A. What was Rutherford's gold experiment and why was it important?
B. Find the energy of a photon with frequency f=3x10^14 Hz.
C. Find the frequency of a photon with energy E=9 units.

Lab: Spectra of Gases

Yesterday we learned that each element emits only certain frequencies of photons. Today we used that idea to identify two unknown gases. In this lab we observed ten different gases through a spectroscope an drew their spectras. I gave you the spectra of two unknown gases. Your job is to compare the spectra of the unknown gases to those you observed in the lab and identify the unknown gases.

This is due on Monday. To help you out, here is a great page with the emission spectra of all elements.

Photon Emission and Absorption

These are the notes from last year, but they will do until I get this year's up. These cover today AND yesterday.

Energy Levels
Energy Levels Continued


Homework:

Find the frequency of the photon emitted or absorbed when an electron:
1. "Falls" from E=15 to E=13. Was this photon emitted or absorbed?
2. "Jumps" from E=10 to E=15. Was this photon emitted or absorbed?
Remember that you can leave Planck's Constant as "h" if you wish.

Particles as Waves and the Heisenberg Uncertainty Principle

Again, these notes are from last year, but they'll do until I get this year's up.

deBroglie Wavelength
Heisenberg Uncertainty Principle

And here is the homework (ignore the repeats; that's for printing purposes):
HW: deBroglie Wavelength

Quanta

These notes are from last year, but they are basically what we did today.

Quanta

And here is the homework (ignore the repeats; that's just for printing purposes)
HW: Energy of a Photon

History of the Model of the Atom

Many, many people have been (and are) involved in the development of models of the atom, but we're only going to talk about 6 developments.

Assigned: Create a time line of the historical development of models of the atom. Remember that a time line should be to scale!
Due: Atom Model assignment, Quarter 1 Crossword.

Atoms Intro

Today we started Unit 4: Quantum Mechanics

Assigned: Atom model assignment
Due: nothing