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Elementary Chemistry Project

  1. May 27, 2004 #1
    OK, I am relatively new to Chemistry, but our school is having a science fair competition soon, and my Chemistry teacher wants us all to do something. Since we are not seasoned warriors of practical Chemistry yet, we are not planning on making bombs, or anything as dangerous and complicated as that. Just to give you a scope of what we are capable of: we have already been acquainted with titration and qualitative analysis, identifying positive/negative ions, etc.

    What we are really interested in, however, is a project involving the theory of Chemistry, preferably something that cannot be found in most Chemistry textbooks. We love moles. However, we do not understand how the number of atoms in a mole can be counted. Maybe we can do a project that lets us count moles? Anyway, I'm looking forward to hearing some great ideas!!
  2. jcsd
  3. May 27, 2004 #2


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    I didn't look at it in too much detail, but http://www.dc.peachnet.edu/~mkim/avogadro.htm [Broken] seems to outline the procedure for an experiment that would allow you to find the number of atoms/molecules in a mole.
    Last edited by a moderator: May 1, 2017
  4. May 27, 2004 #3


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    If you take a balloon with a little bit of water in it, tie it up and put it in a microwave, the water boils to make steam, which inflates the balloon - this looks really neat.

    The number of moles of water remains constant, but volume increases by about thousand times when a liquid becomes a gas. You can use the PV = nRT Gas equation to calculate the volume of one mole of water vapor. You can also calculate the volume of 1 mole of liquid water from the molecular weight (18gm==18cc). From these 2 equations you can figure out how much liquid to use to fill the balloon with say, 1 liter of vapor. The calculation adds to the the quality of the experiment.

    WARNING : You want to be very careful with this. Start with less than the calculated amount of water. Remember, you are dealing with boiling water and steam. Don't leave the microwave on for more than a few seconds after the balloon inflates. Be really careful if you have to wipe off water, it could be very hot. After you've done the experiment, don't immediately grab the balloon with your fingers, you will get burned. Also, don't immediately put your face in front of the open microwave. There may be some real hot steam ready to come out. I strongly suggest you try this (if you even want to) first with adult supervision.

    If you have any questions, send me a message.
    Last edited: May 27, 2004
  5. Jun 4, 2004 #4
    Great Ideas guys! I'll be trying them out after my exams. However, I would like to know about making soap from fats. I have a found a site online that teaches you how to make soaps, but do any of you have any suggestions as to which kind of fat is best? I watched Fight Club some time ago and they said Human Fat was pretty good? In the movie, the Brad Pitt character also says something about it being possible to make explosives from using just household items. Anyone care to tell me how this is done?

    EDIT: Just in case some of you are worried, I'm not at all considering blowing up anything. It's just that not being in the know of making bombs (from household items) has been nagging me for a while.
    Last edited: Jun 4, 2004
  6. Jun 4, 2004 #5


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    I suppose your project can be regarding the history of the mole. However, many chemist these days find the mole inefficient, especially in relevance to pharmaceuticals where such a large number (6.022...) is inconvenient since the latter deals with small numbers of molecules.

    Going into depth in any theory will be somewhat complex. Here's a feasible one to work on. Read Van't Hoff's Nobel lecture



    http://groups.msn.com/GeneralChemistryHomework/hoff.msnw [Broken]

    http://groups.msn.com/GeneralChemistryHomework [Broken]
    Last edited by a moderator: May 1, 2017
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