�The System� by q7c0e236

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									“The System,” an inquiry lab from ChemTrek by Stephen Thompson, 1990.




                         will be placed within your control at the start of the laboratory.
                                         Please read this brief introduction
                                                      BEFORE
                                        you begin to exercise your authority.
                                                Unlike Dr. Science,
                                                   I have a Ph.D.,
                                       and since I am the Original Controller,
                                  I wish to challenge you by setting a few goals
                       and a few rules. Of course, if you don’t wish to work towards goals
                                           and if you wish to break rules,
                                     then you may do so. However, since I am
                                              the Original Controller,
                                    I simply request that you tell me in writing
                             what motivates you to be so outrageous and antisocial.


    1. To find out what “The System” will do.
    2. To interpret what “The System” does.
    3. To tell the Original Controller how you found out.


1. You may do anything you wish to “The System,” but remember that whatever you do will change it and you.
2. You cannot remove the cap until the Original Controller is convinced that you know what you are doing.
     One further request. Since this institution purports to be one of Higher Education, The Original Controller
      begs you to keep a real-time record of your day with “The System.” After all, this is the beginning of your
      life as a true thinker and natural scientist.
       Are you sitting comfortably? Then we shall begin.

 “The System” is in front of you. Don’t touch—yet. Why don’t you record its birthdate (and time). (Then at
  least you will know when it gets old.)
 Don’t worry, the Original Controller has an English (some call it weird) sense of humor, as well as a Ph.D.!
 Don’t touch—yet. Why not try to describe “The System” as accurately as you can—for example,
                                             What is it standing on?
                                           Are the lights switched on?
                                     What is the stuff you can see through?
                                    How do you know that? What visual cues
                                      tell you that something is not solid?
                                                What shape is it?
                                            What are its dimensions?
                                    Can you find that out without touching it?
 Make a simple drawing—sometimes pictures are worth more than a million words (Confucius, not Controller).
 Are you writing all this down? Or are you bored?
 Now write down the goals in your lab notebook.



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 You have the goals and a lot of facts. Try to interpret some of these observations with the goals in mind—e.g.,
  what’s happening to all that energy pouring into “The System” in the form of light? What’s the ratio of space
  to liquid?
 Don’t you find it tough to really see “The System” well when it’s on a black background? Before you move it,
  think about that. If it were milk, it would be easy to see, right?
 Why not move it to a white background? Hold it! How are you going to do that? With your fingers—then
  which part to touch? What temperature are fingers? For that matter, what temperature is the system? What
  makes you think that it’s at room temperature? I would like to know! Note how you do it.
 If it’s on a white background now, you should make a note in your book that it now has about 50 times more
  light going into (through) it.
 Anything peculiar happen when you moved it?
 Are you still sitting in the same place? Perhaps if you moved and looked, it might change your point of view!
  Places where two things meet—interfaces—are often revealing.
 OK, let’s get radical—better note the time. If “The System” self-destructs in a blue flash, at least you will
  know when it died. Pick it up and give it a small motion—small! What happened? The reason I am suggesting
  small is that small perturbations can be increased. Large perturbations could finish it.
 Write down how you picked it up.
 Shake “The System” gently. Watch (you have a hand lens). Now describe exactly what you saw and exactly
  how you shook it. Your shake is unique. This is important because nobody shakes like you do. Did the stuff at
  the bottom touch the cap?
 Try that again, this time a little harder. How much kinetic energy do you think you gave it? No, seriously—
  how does one measure human shakes?
 Did you create any bubbles? Did you watch them? Perhaps bubble power is the secret.
 There must be an explanation for that change. For example, here are three that seem reasonable:
       1. There is something on the cap that catalyzes the change.
       2. Kinetic energy from the motion makes the change happen.
       3. The change won’t happen in the dark.
 What’s your interpretation? Then you must design simple experiments to prove yours and disprove mine
  (stated below). Remember the K.I.S.S. principle!
                                       I think that there are really 2 liquids!
 Back to bubbles for a minute. What is a bubble in “The System?” Draw one. What happens when one bursts?
 Perhaps you need to design a standard shake so that you can reproduce it. The Original Controller’s standard
  shake involves holding the cap firmly between the thumb and the second finger with the index finger on top to
  steady it (I am right handed.) Hold the left hand out at the side of the system and at the height of the cap, palm
  down. Lift “The System” up about 1 cm. Now sharply shake in a vertical direction so that the bottom of “The
  System” reaches the height of the left hand and then descends back down to about 1 cm above the table. Then
  set it down.
 Try it again. Describe the dynamics, and don’t forget to keep a record of “System,” shakes.
 What are those strange structures inside “The System?” Are they reproducible? Describe, or better still, draw
  what happens spatially—i.e., the bottom half versus the top half.
 Perhaps it’s time to get real scientific! Since radical things happen when you shake “The System,” then a
  graph of number of shakes versus time might be most enlightening. Time for what? Time for the bottom part
  to clear. You will need a clock or watch with a second hand to do this. Try up to about 6 standard shakes all at
  once. At the same time, try to assess the intensity of color in “The System.”
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 On the lined paper in your book, make a rough graph of the number of standard shakes versus the time to
  change back. On the same graph, plot number of standard shakes versus intensity of color (approximately).
 How old is “The System” now?
 Do you like music? (The Original Controller (O.C.) is a Grateful Dead freak—you know, the only good freak
  is a dead freak!) Try this one. Tap the system several times with a pen or pencil and listen to the sound. Now
  shake the system and immediately tap again. Notice any difference? It’s almost an octave! By the way, this is
  one way to beat “The System.”
 How about a total review of the facts? Why not do what chemists do? Choose some simple symbols for
  things—e.g., C could mean colorless,  could mean change, G could be gas. Now organize the symbols into a
  scheme of things that matches what the system does. What you are doing now is trying to create a model.
 Does your scheme fit all the facts (observations)?
 Do you think “The System” involves physical change or chemical change, or both? What observations support
  your opinion? Let’s see if you can make a prediction (in writing). Describe what you think will actually
  happen if “The System” is cooled or heated. Think this through with your scheme in mind.
 Why not see if you are right? Cool the system first. This is less dangerous than heating it. Make an ice bath
  (about 50% ice and 50% water) in a styrofoam coffee cup. If you cool things, remember that the process takes
  time. Why? What experiment(s) are you going to do to test your prediction? OK, do it (them).
 Don’t forget—now it’s old and cold.
 Were you right?
 Here’s a non sequitur. Do you think that light has had any effect on “The System?” Make a brief list of what
  light can do to things.
 If you ask pleasantly, the Original Controller’s assistant will show you another “System” untouched by human
  mind or hand. Make a comparison of the two “Systems”—yours and the untouched one. Remember this
  significant fact —the untouched “System” has been standing in the room light since the start of the laboratory.
 Now how about some risky business? What will happen if “The System” is heated? Bang! Before you send
  “System” shrapnel whistling through your fellow scientists (O.C. is behind the wall), explain in your notes
  why heating things like “The System” will sometimes produce explosions.
 Perhaps it is time to gain access to “The System”—i.e., remove the cap. Hold it! Before you undo
    anything, think about what could happen. How you take the cap off may tell you a lot about “The
    System.” Let’s look at some possibilities. Well,
        1. The cap won’t come off.
        2. There is a potential vacuum in “The System” and ordinary air will rush in.
        3. “The System” contains a gas (or gases) that is/are denser than air and nothing will happen. Or it might
           contain a gas (or gases) less dense than air and the gas (or gases) will fly away never to be smelled
           again.
        4. “The System” might be toxic.
 How about undoing the cap carefully and slowly so that you can watch what happens in that ring of liquid
  that’s always in the area of the cap thread? Listen, smell and watch for changes—but don’t snort it! Use a
  paper towel to wipe the cap and the outside top of “The System” dry.


 Now what? Well, you now have access to the inside of “The System,” which will be referred to as a “system”,
  since it is only one of any number of “systems” in the universe. The question is, do you have to repeat
  everything you already did, or can you make some assumptions about the relationship between “The System”
  and “a system”? Try. What are your assumptions? (Hint—“The System” became “a system” when the cap was
  removed.)
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 Do you think that the space above the liquid in the original vial was air?
 Now you can clone “The System” and make little “systems.” “Small is beautiful” is a motto to be revered.
  Perhaps it is worth sacrificing a little one in the cause of science. Use a plastic pipet to transfer a small
  “system” to a small vial. Make sure there is no cap on the small vial. Light a match and hold it in one hand
  while you grasp the vial containing the small “system” with tweezers in your other hand. Now bring the match
  under the vial and heat it for five seconds.



 I know the vial gets black. Explain why it gets black. Wipe the black away. Now what happened? Will the
  little “system” still change?
 OK. Let’s take a break. During the break, please introduce yourself to your neighbors so that you can
  communicate on a first-name basis. Compare your scheme with theirs. You can incorporate any features of
  their scheme(s) into yours if you like. However, you need to make sure that the original vials (“The System”)
  of your neighbors are very like yours and you must get their permission in writing. An acknowledgment in
  your notes might also be courteous. They must do the same for you. Anyway, it’s always nice to meet such
  good-looking people in the same course!
 Let’s get back to what happened to the little “system.” Make a brief list of what happens when things are
  heated. What is heat anyway? Add an extra symbol and step to your scheme on the basis of what happened
  with heat.
 Slight problem, however. What color was the little “system” when you put a match to it? See what I mean?
 Back to the original vial—“The System.” Put the cap on and stand it in some warm water in a styrofoam cup
  for a few minutes. Now what color is it? Give it one standard shake and time how long it takes to go back to its
  original color. Compare this time with the previous one carried out at room temperature.
 Now you can do an experiment that has some very interesting practical applications. Remove the cap and dry
  the glass and cap with a paper towel. Use a plastic pipet to suck up some fresh cold water (you will find it in a
  beaker at Reagent Central). Add the water to “The System” liquid without making bubbles. Stir gently. Record
  what happens. Why not try that again? Is the effect reproducible? Now, why does “The System” do that?
 You have added enough water to roughly double the original volume. Warm it with your hands to make sure
  it’s back to about room temperature. Now put the cap on and give it one standard shake. Time how long it
  takes to go back to its original color. Interpret your result. Does your explanation fit into the scheme you
  proposed earlier?
 Happiness. We are going to divide the class up into four discussion groups. You get to meet more good
  looking scientists! Once you are in your group, introduce yourselves and discuss “The System.” Make a
  collective decision on the following two issues:
        1. What general scheme of symbols best describes what “The System” will do?
        2. How many components are there inside “The System?”
 Write the group decisions in your notes. Elect a spokesperson.
 Your instructor, the assistant controller, will now organize a mini-meeting in order to astound you with
  demonstrations of such bravery and skill that you will be truly thankful to be in this chemistry course. Your
  spokesperson will be asked to render public the collective wisdom of your group.
                                                 * * Meeting * *
 You are now promoted to scientist first-class. At Reagent Central there are, in beautifully labeled containers,
  all of the components of




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 The goal is for you to decide within your collective group and by experiments


                          which combination of components is responsible for the
                         phenomenon that you have observed while interacting with
                                             “The System.”



 You
     are
        confused.
                     

OK, let me give an example. What combination (apart from the Grateful Dead and good food) makes the blues go
away?
Conclusion
“The System” will be revealed to you in all its sophisticated detail at the end of the laboratory. Any questions you
have will be answered fully to the best of our ability. We will also give you a glimpse of the incredible diversity
of practical applications of “The System.” Components can be found in Japanese food stores, in sewage treatment
plants, in large-animal veterinary clinics, in recombinant DNA laboratories, in cancer treatment programs, and in
erasable laser holograms. We do have one request of you before you leave the laboratory. This is a large
chemistry course, and I am sure that you feel, as we do, that to reveal any information of what transpires in this
laboratory to other students would truly deprive them of a scientific experience almost equal to a personal
appearance on NOVA. The Original Controller begs you to sign the affidavit below 




  I, (print name)                                                       Student No.

  Possible College Major                                                Star Sign

  Musical preference

  Will not reveal anything (verbally or in writing) of what transpired in the
  laboratory concerning “The System” to any other student, Controller, or friend
  until after the laboratory has been completed by all students in the course.



  Signature                                                                      Date

Please tear this out and give it to your instructor. It will be kept on record for at least 17 years.




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