The Chemistry Workshop          Honors Chemistry           Homework 4/27 - May 8

Monday, 4/27--Read Page 384 & answer these questions.

Also.....if you need to, complete the chapter 13 review you began in class today.

Questions 57-63 are from "Chemistry Serving Society: Lasers At Work" on page 384.

57. What is a laser?

58. List 2 ways in which laser light is different from ordinary white light.

59. In what way is a gas laser similar to a neon sign?

60. Describe how a gas tube of a laser causes light to be emitted with the same energy & direction.

61. (a) Light from a flashlight loses intensity the farther it gets from the source.  Why.   (b) Explain why laser light does not do this.

62. Describe how the lasers in CD players and barcode scanners work.

63. Why is laser surgery usually "bloodless" surgery?

64. One of the lines in the emission spectrum of hydrogen has a wavelength of 0.656 μm. 

        (a) What is the color of this light?    (b) Calculate the frequency of this light.

65. Arrange the following in order of decreasing wavelength:  

        --The waves from Mr. P's favorite radio station WMJI.

        --Ultraviolet waves from the sun will burn Mr. P's bald spot this Summer.

        --Infrared waves coming from the heat lamps keeping Mr. P's steak warm until the waitress brings it to his table.

        --Gamma rays shooting through Mr. P's body as he drives past the nuclear waste dump at 3 Mile Island.

        --The microwaves that Mr. P used to cook his popcorn in the prep room attached to room 255.

        --The radar waves used by the CHP officer who last gave Mr. P a speeding ticket.

Tuesday, 4/28--Complete the Chapter 13 Review too!.

Wednesday, April 29--Read section 14.1 and answer these questions.

1.  (a)Explain why it became important, in the 2nd half of the 19th century, to organize the chemical elements into a useful table.

        (b) Who was the scientist that did this?     (c) How are the elements arranged in the modern periodic table?

2.  Study the periodic table, figure 14.2, figure 14.5 and pages 394 & 395:

        (a) Name the 6 Alkali Metals         (b) What is their "Group Number" on the periodic table?         

        (c) How many electrons do they have in their outermost energy level?

        (d) Name the 6 Alkaline Earth Metals       (e) What is their "Group Number" on the periodic table?            

        (f) How many electrons do they have in their outermost energy level?

        (g) Name the 40 Transition metals             (h) What are their "Group Numbers" on the periodic table?       

        (i) What is the notable characteristic of their electron configurations?

        (j) Name the 6 Noble Gases           (k) What is their "Group Number" on the periodic table?         

        (l) How many electrons do they have in their outermost energy level?

        (m) Name the 14 Lanthanides          (n) What is the notable characteristic of their electron configurations?

        (o) Name the 14 Actinides          (p) What is the notable characteristic of their electron configurations?

        (q) When we refer to the "s" block on the periodic table, what do we mean?

        (r) When we refer to the "p" block on the periodic table, what do we mean?

        (s) When we refer to the "d" block on the periodic table, what do we mean?

        (t) When we refer to the "f" block on the periodic table, what do we mean?

Thursday, April 30--Read section 14.2 and answer these questions.

3.  (a) Why does an atom not have a sharply-defined boundary?     (b) Describe 2 ways to determine atomic size.

4.  Define or describe these terms:  X-ray Diffraction, Atomic Radius, Picometer

5.  Study Figures 14.7 - 14.10.

      Atomic Size:

        (a) Write the symbols and atomic radius of the elements in the row that starts with Lithium and ends with Neon.

        (b) Write the symbols and atomic radius of the elements in the row that starts with Potassium and ends with Krypton.

        (c) Make a general statement regarding how the atomic size varies as you go across a row (from left-to-right) on the periodic         table.

        (d) Write the symbols and atomic radius of the elements in the column that has Hydrogen at the top & Cesium at the bottom.

        (e) Write the symbols and atomic radius of the elements in the column that has Oxygen at the top & Polonium at the bottom.

        (f) Make a general statement regarding how the atomic size varies as you go down a column in the periodic table.

      Ionic Size:

        (g) Compare the sizes of Li & Li⁺     (h) Compare the sizes of Sn & Sn⁴⁺     (i) Compare the sizes of Al & Al³⁺

        (j) Make a general statement regarding how atomic size changes when atoms lose electrons to become positive ions.

        (k) Compare the sizes of Br & Br^-     (l) Compare the sizes of O & O^2-     (m) Compare the sizes of As & As^3-

        (n) Make a general statement regarding how atomic size changes when atoms gain electrons to become negative ions.

Friday, May 1 & over the weekend--Read section 14.2 and answer these questions.

6.  Define or describe these terms:  Ionization Energy, Electronegativity

7.  Study Figures 14.11 & 14.12 and Table 14.1:

        (a) Write the symbols and 1st ionization energies of the elements in the row that starts with Lithium and ends with Neon.

        (b) Write the symbols and 1st ionization energies of the elements in the row that starts with Sodium and ends with Argon.

        (c) Make a general statement regarding how the ionization energy size varies as you go across a row on the periodic table.

                (d) Write the symbols and 1st ionization energies of the elements Lithium, Sodium, and Potassium.

        (e) Write the symbols and 1st ionization energies of the elements Beryllium, Magnesium, and Calcium.

        (f) Make a general statement regarding how the ionization energy size varies as you go down a column on the periodic table.

8.  Study Table 14.2:

        (a) Write the symbols and electronegativities of the elements in the row that starts with Lithium and ends with Fluorine.

        (b) Write the symbols and electronegativities of the elements in the row that starts with Rubidium and ends with Iodine.

        (c) Make a general statement regarding how the electronegativity of atoms varies as you go across a row on the periodic table.

        (d) Write the symbols and electronegativities of the elements in the column that starts with Hydrogen and ends with Cesium.

        (e) Write the symbols and electronegativities of the elements in the column that starts with Fluorine and ends with Iodine.

        (f) Make a general statement regarding how the electronegativity varies as you go down a column on the periodic table.

Monday, May 4--Read section 14.2 and answer these questions.

9.  Summarize these periodic trends:

        (a) Atomic Size as you go across a row of the periodic table.

        (b) Ionization Energy as you go across a row of the periodic table.

        (c) Electronegativity size as you go across a row of the periodic table.

        (d) Atomic size as you go down a column of the periodic table.

        (e) Ionization Energy as you go down a column of the periodic table.

        (f) Electronegativity as you go down a column of the periodic table.

        (g) Atomic size as elements gain electrons to become negative ions.

        (h) Atomic size as elements lose electrons to become positive ions.

Questions 10-15 are from "Chemistry Serving Industry: Big Jobs For Little Devices"

10. (a) What was ENIAC?      (b) When was it built?     (c) How big was it?     (d) How much could it do by today's standards?

11. What made "miniaturization" possible in the electronics industry?

12. (a) What are "semiconductors"?     (b) Name 3 well-known semiconductors?

13. Explain why crystals of "contaminated" as compared to "pure" semiconductors are used in the electronics industry.

14. (a) What is "doping"?    (b) Explain how an n-type semiconductor is made.    (c) Explain how a p-type semiconductor is made.

15. What is a computer "chip" made from?

Tuesday, May 5 -- Complete the handout given to you in class today.

Wednesday, May 6--Chapter 14 Review, Part I

1.  (a) Name 3 Noble Gases     (b) Name 3 Lanthanides     (c) Name 3 Alkali Metals     (d) Name 3 Actinides  

     (e) Name 3 Representative Elements     (f) Name 3 Alkaline Earth Metals

2.  Write electron configurations for these atoms and ions.  (a) Sn     (b) Cs⁺     (c) Hf     (d) Br^-     (e) Cd

3.  State which is smaller and explain WHY.  (a) Ca or Sr     (b) Sn or Sb     (c) Pr or Pa     (d) Br or Se

4.  Indicate which element has the higher first ionization energy and explain WHY. (a) Si or P   (b) Rb or Cs  (c) P or S

5.  Indicate which element has the higher electron affinity and explain WHY.  (a) N or O     (b) S or Se     (c) K or Ar

6.  Indicate which element has the higher electronegativity and explain WHY.  (a) F or Br      (b) O or C    (c) Na or Cl

7.  Explain what "effective nuclear charge" is, and HOW we use it.

8.  Metals have higher 1st ionization energies than non-metals.  True or False?  EXPLAIN your answer.

9.  There is a large increase between the first and second ionization energies of the Alkali Metals.  EXPLAIN.

10. All of these atoms have ten electrons.  Arrange them in order from smallest to largest.  Ne, Al³⁺, F^-, Na⁺, N^3-, Mg⁺⁺, O^2-  

11. Indicate which ion is smaller and explain WHY.  (a) Br^- or Cl^-     (b) Ca⁺⁺ or K⁺     (c) K⁺ or Cl^-      (d) Mg⁺ or Mg⁺⁺

12. Atomic size increases as you go from K to Kr.  True or False?  EXPLAIN your answer.

13. Atomic size increases as you go from K to Fr.  True or False?  EXPLAIN your answer.

14. Ionization Energy decreases as you go from K to Kr.  True or False?  EXPLAIN your answer.

15. Ionization Energy decreases as you go from K to Fr.  True or False?  EXPLAIN your answer.

Thursday, May 7--Chapter 14 Review, Part II -- The Joy, The Boundless Ecstasy of Vocabulary

Define or describe these Chapter 13 & 14 terms:

1.  Emission Spectrum                                         9.  Hund's Rule                                                     17. Noble Gases

2.  Atomic Orbital                                 10. Pauli Exclusion Principle                               18. Representative Elements

3.  Aufbau Principle                                             11. Photoelectric Effect                                       19. Transition Metals

4.  Electromagnetic Radiation                             12. Photon                                                             20. Lanthanides

5.  Electron Configuration                                   13. Actinides                                                         21. Ionization Energy

6.  Energy Level                                                    14. Alkali Metals                                                  22. Valence Electrons

7.  Frequency                                                        15. Alkaline Earth Metals                                    23. Electronegativity

8.  Ground State                                                    16. Atomic Radius                                                24. Electron Affinity

What to Study for Friday's Chapter 13/14 Exam:

·         Review Homework Questions.

·         Review Vocabulary terms listed on pages 385 & 408.

·         Know what the Giants did to help us learn about the structure of the atom.

·         --Dalton, Thomson, Rutherford, Bohr, Planck, de Broglie, Heisenberg, Einstein, Schroedinger

·         Know what the s, p, & d orbitals look like.

·         Know how to do electron configurations for atoms and ions.

·         Know how do wave calculations for energy, frequency, and wavelength.

·         Have a working knowledge of where X-rays, Microwaves, & etc. are on the electromagnetic spectrum (page 373).

·         Have a working knowledge of the Periodic Table.

·         Know the names of the chemical families.

·         Have a working knowledge of the equation F = k(q₁)(q₂)/r²

·         Have a working knowledge of periodic trends:

·         --Atomic & ionic size, Ionization Energy, Electron Affinity, Electronegativity

·        Go through chapters 13 & 14 and look at every illustration.  Be sure you know what each illustration is showing you.