The Chemistry Workshop      Honors Chemistry Homework     Weeks of 4/13 & 4/20

Monday, 4/13--Complete the Calculations Party Handout and answer these questions from section 12.5 -- "Chemistry Serving Industry--Diving Can Be A Gas".

62. Explain how a diver's equipment allows her to breathe deep under water where the pressure on the body is quite high.

63. What is the "problem" with the gases you breathe when diving even to moderate depths?

64. What is nitrogen narcosis?

65. (a) What causes "the bends"?      (b) How can the bends be avoided?

66. When diving really deep, how are the problems with nitrogen avoided?

67. Describe (a) Nitrox  (b) Heliox, and (c) Trimix.  Pretty cool stuff!

Tuesday, 4/14 CLASSWORK--Complete Chapter 12 Review I

1.  What are the 4 main assumptions of the Kinetic Molecular Theory of gases?

2.  How is the kinetic energy of a gas related to temperature?

3.  Explain, at the molecular level, why the pressure increases as temperature increases.

4.  Explain why gases are compressible, while liquids are not.

5.  Describe how pressure is related to temperature at constant volume & moles of gas.

6.  Describe how pressure is related to volume at constant temperature & moles of gas.

7.  Describe how pressure is related to moles of gas at constant volume & temperature.

8.  Describe how volume is related to temperature at constant pressure & moles of gas.

9.  Describe how volume is related to moles of gas at constant pressure & temperature.

10. Why do you use Kelvin temperature and not °C or °F in gas law calculations?

11. Describe, at the molecular level, what happens to a balloon full of gas when you put it into a freezer.

12. Gases expand to fill a vacuum, yet, the Earth's atmosphere does not escape into the near vacuum of outer space. Explain.

13. Inside a "Thermos" bottle is 2 layers of glass separated by a vacuum. So when you fill it with hot chocolate, it stays hot rather than losing heat to the environment. Explain.

14. What is (a) Charles's Law    (b) Boyle's Law    (c) Gay-Lussac's Law     (d) The Combined Gas Law

15. (a) What is the Ideal Gas Law?   (b) What is "R" called?   

16. What is the numerical value of "R" when pressure is in (a) atm (b) mm Hg (c) kPa?

17. Show how each of the above laws can come from the Ideal Gas Law.

Tuesday, 4/14 HOMEWORK--Complete Chapter 12 Review II

1.  Describe some differences between "ideal" gases and "real" gases.

2.  What is Avogadro's Hypothesis?

3.  Explain Dalton's Law of Partial Pressure.

4.  Derive Graham's Law from the fact that if Ne gas and Xe gas molecules are at the same temperature,

then KE_Ne = KE_Xe, and 1/2 M_NeV_Ne² = 1/2 M_XeV_Xe².

5.  How is the partial pressure of a gas in a mixture calculated?

6.  What assumption from the KMT is responsible for the idea that every gas has a molar volume of 22.4 L?

7.  At 27 °C, the rate of effusion for CO is the same as the rate of effusion for N₂. Explain.

8.  Explain the difference between diffusion and effusion.

9.  Rank these gases from fastest to effuse to slowest to effuse & explain why: (a) C1₂   (b) NO₂   (c) NH₃   (d) N₂

10. If the Kelvin temperature of a gas is tripled and the volume is doubled, the new pressure will be??

11. 10 grams of a gas is in a 4.5 L container at 45 °C. Explain what happens to the pressure if you:

(a) add 3 grams of the same gas.               (d) decrease the volume of the container.        (g) heat the gas.

(b) cool the gas.                                           (e) add 3 grams of a different gas.

(c) enlarge the container.                            (f) remove 3 grams of gas.

12. Under what conditions does a "real" gas behave like an "ideal"?

13. You take an empty metal paint thinner can, put in 1/4 cup of water, and, leaving the cap off, bring it to a boil. You quickly screw on the cap while the hot water is inside the can. You let the can cool on your kitchen counter. Describe what happens over the next half hour and why it happens.

14. If you did the same process with an empty dry can, would the same thing happen as it cooled? Explain why or why not.

15. Describe the relationship between the plotted variables for the 6 graphs below:

        (a) A & B     (b) C & D     (c) E & F      (d) G & H     (e) I & J      (f) K & L

Chapter 12 Test is Wednesday, 4/15 & Thursday, 4/16

Calculations & Fill-In/Explanations

Thursday, 4/16, Friday, 4/17 & over the weekend--Read section 13.1 and answer these questions.

Extra Credit opportunity: Complete the "Discover It! activity on page 360.  Your observations must be thorough to receive credit.

1.  Describe the structure of an atom as you know it now.

2.  Why is knowledge of the electronic structure of atoms important to know?

3.  What did John Dalton think about the structure of the atom?

Study figures 13-2, 13-3, and pages 361-364 to answer question 4.

4.    (a) What did J. J. Thompson discover?

        (b) Summarize Thompson's model of the atom.

        (c) What did Ernest Rutherford discover?

        (d) Summarize Rutherford's model of the atom.

        (e) Summarize the model put forth by Niels Bohr.

        (f) What are "energy levels" in Bohr's model;?

        (g) Why are these energy levels important to his model?

        (h) What is a "quantum" of energy?

        (i) How are the energy levels arranged in an atom?

        (j) Why is it easier for an electron in the 4th energy level to escape from an atom that an electron in the 1st energy level?

        (k) What was Erwin Schrodinger's contribution to this discussion?

        (l) What is the most important concept in Schrodinger's quantum mechanical model of the atom?

        (m) Summarize Schrodinger's model.

Study Table 13.1, Figures 13.4 & 13.5, and pages 364-366 to answer question 5.

5.    (a) What are "energy Levels" in an atom?

        (b) Which "quantum number" denotes an electron's energy level?

        (c) Which values can "n" have?

        (d) What intelligent statement can you make about an electron with n = 2 compared to an electron with n = 4?

        (e) How many sublevels are in the 1st energy level (n = 1)?

        (f) What is the name of the type of sublevel in the 1st energy level?

        (g) What is an "atomic orbital"?

        (h) Describe the shape of an "s" orbital.

        (i) How many sublevels are in the 2nd energy level (n = 2)?

        (j) What are the names of the types of sublevels in the 2nd energy level?

        (k) Describe the shapes of the "s" & "p" orbitals.

        (l) How many sublevels are in the 3rd energy level (n = 3)?

        (m) What are the names of the types of sublevels in the 3rd energy level?

        (n)  Describe the shapes of the "s" "p" and "d" orbitals.

        (o) How many sublevels are in the 4th energy level (n = 4)?

        (p) What are the names of the types of sublevels in the 4th energy level?

        (q) Why are there no drawings of "f" orbitals?

        (r) How many orbitals are in the 2s sublevel?

        (s) How many orbitals are in the 3d sublevel?

        (t) How many orbitals are in the 4p sublevel?

        (u) How many orbitals are in the 4f sublevel?

        (v) If each orbital can hold 2 electrons, how many electrons can be in the 4p sublevel?

        (w) If each orbital can hold 2 electrons, how many electrons can be in the 2s sublevel?

        (x) If each orbital can hold 2 electrons, how many electrons can be in the 3d sublevel?

        (y) If each orbital can hold 2 electrons, how many electrons can be in the 3s sublevel?

        (z) If each orbital can hold 2 electrons, how many electrons can be in the 4f sublevel?

Now I know my abc's, tell me what you think of me!

Monday, 4/20--Read section 13.2 and answer these questions.

6.  Summarize the Aufbau Principle.

7.  Summarize the Pauli Exclusion Principle.

8.  Summarize Hund's Rule.

9.  Write electron configurations for these atoms:  (a) Mg     (b) Cl     (c) Ba     (d) I     (e) He

10. Why is the electron configuration for Cu = 1s².....3d¹⁰ 4s¹ and not 1s²...3d⁹4s²?

11. Write electron configurations for these atoms:  (a) Ti     (b) Ag     (c) Co     (d) Zn    (e) Cr

Now lets start looking at ions.  Positive ions have LOST electrons.  Negative ions have GAINED electrons.  Be sure you account for these in the electron configuration.

12. Write electron configurations for these atoms & ions: 

        (a) Ca & Ca²⁺     (b) F & F^-    (c) K & K⁺     (d) Br & Br^-     (e) Al & Al³⁺

Tuesday, 4/21--Re-visit sections 13.1 & 13.2 and answer these questions.

13. Which subatomic particles did Thompson include in his "plum pudding" model of the atom?

14. How did Bohr answer the objection that an electron traveling in a circular orbit would radiate energy and fall into the nucleus?

15. What is the significance of the boundary of the electron cloud?

16. What is an atomic orbital?

17. Name the 4 different kinds of orbitals.

18. Describe the shapes of the 4 different kinds of orbitals.

19. Sketch these orbitals: (a) 1s      (b) 2s     (c) 3p     (d) 4f

20. Give the electron configurations for these elements:  (a) Boron     (b) S     (c) #38     (d) Hg

21. State how many electrons are in these sublevels.  If the sublevel can not exist, just say "not allowed Bozo":

        (a) 1p     (b) 3d     (c) 2s     (d) 4f     (e) 2f     (f) 2d     (g) 4s     (h) 5p

22. How many electrons can be in:

        (a) the 1st energy level of an atom?     (b) the second energy level?   (c) the 3rd energy level?     (d) the 4th energy level?

23. Write electron configurations for these ions:   (a) O^2-     (b) Sr²⁺     (c) Co³⁺     (d) I^-

Wednesday, 4/22--Read Section 13.3 and answer these questions.

24. Define these terms:     Electromagnetic Radiation, Amplitude, Wavelength, Frequency, Hertz, Spectrum, Atomic Emission Spectrum.

25. (a) What is the speed of light?   (b) is it the same in water & air as it is in a vacuum?

26. (a) Write the equation that shows the relationship between wavelength & frequency.  (b) What kind of proportion is this?

Study figures 13.8-13.12 before answering questions 27-32.

27. Rank these "types" of light in terms of increasing frequency.

        Microwaves, Radio waves, Gamma rays, Ultraviolet, Radar, Cosmic rays, Infrared, X-rays

28. Rank these "types" of light in terms of increasing wavelength.

        Microwaves, Radio waves, Gamma rays, Ultraviolet, Radar, Cosmic rays, Infrared, X-rays

29. Describe the difference between the spectrum you get from sunlight and the emission spectrum of hydrogen.

30. What does each line in an emission spectrum stand for?

31. What "type" of light corresponds to each frequency?

        (a) 10¹² Hz    (b) 10²⁰ Hz     (c) 10⁷ Hz     (d) 10¹⁵ Hz     (e) 10¹⁴ Hz

32. What "type" of light corresponds to each wavelength?

        (a) 10 nm     (b) 10 μm     (c) 10 cm     (d) 10 m     (e) .001 nm

Thursday, 4/23--Read Section 13.3 and answer these questions.

Study Sample Problem 13-2 and work practice problems 11 &12.

33. Convert these wavelengths to frequencies:   (a) 5.97 μm     (b) 37.6 mm     (c) 1.43 x 10^-4 nm

34. Convert these frequencies to wavelengths:     (d) 6.89 x 10²⁰ Hz      (e) 1.69 x 10⁸ Hz     (f) 5.67 x 10¹⁴ Hz    

35. What "type" of light corresponds to each frequency/wavelength (a-f) in questions 33 & 34?

36. Read "Link to Astronomy" on page 376 & describe how helium was discovered to exist on the sun.

37. Why can't classical physics explain emission spectra of atoms?

38. (a) Who came up with the idea that explains emission spectra?     (b) What problem was he working on at the time?

39. (a) What is Planck's equation?     (b) What is the value of Planck's constant, h?     (c) What is a joule, J?

40. Planck's "quantum" theory is hard for most people to understand.  Explain how it applies to heating water from 0°C to 100 °C.

41. (a) What is a Photon?     (b) How is its energy quantized?

42. Study figure 3.15 and pages 377 & 379.

        (a) Describe the Photoelectric Effect.     (b) Why can't classical physics explain it?     (c) How did Einstein explain it?    

        (d) What is the difference between light's intensity & its energy?     (e) How does the photoelectric effect illustrate quantum theory?     (f) How does the ping pong ball/golf ball/billiard ball analogy on page 379 explain the photoelectric effect so one can understand it?

Friday, 4/24 & over the weekend--Read Section 13.3 and answer these questions.

43. Study page 378 & complete practice problems A-D on the CheMath page.

Study sample problem 13-3 and work practice problems 13 & 14.

44. Calculate the energy of photons with these frequencies:  (a) 6.89 x 10¹³ Hz     (b) 9.11 x 10²⁰ Hz

45. Calculate the energy of photons with these wavelengths:  (a) 5.97 μm     (b) 37.6 mm

46. Calculate the wavelength of photons with these energies:  (a) 3.86 x 10^-14 J     (b) 1.78 x 10^-24 J

47. Calculate the frequency of photons with these energies:  (c) 5.56 x 10^-16 J     (d) 4.71 x 10^-20 J

48. What "type" of light corresponds to each energy (a-d) in questions 47 & 48?

49. Explain the difference between a ground state electron and an electron in a excited state.

50. Explain the difference between an atom's absorption spectrum and its emission spectrum. (thought question)

51. Study figure 13.17 and pages 379-380.  Describe what must happen in a Hydrogen atom to give these emission spectra:

        (a) Lyman Series?     (b) Balmer Series?     (c) Paschen Series?

52. Give 2 reasons why the Bohr's model was only partially successful and why the search for a complete model continued.

53. (a) What was Louis de Broglie's brilliant idea?     (b) What is de Broglie's equation?      (c) What do "m" and "v" stand for?

54. Since all particles move with wave motion, how come normal every-day objects, like a baseball, appear to travel in a straight line?

55. Summarize the 2 main differences between the explanation of phenomena by classical physics (classical mechanics) and the new field of quantum mechanics.

56. Study figure 13.19 and page 382.  (a) State the Heisenberg Uncertainty Principle.   (b) Why is it true, when applied to tiny particles like electrons moving inside of atoms?