Tuesday, January 8, 2013

I have to talk to some middle schoolers about chemistry -- what should I do?

A couple of months ago, I volunteered to give a talk on "Career Day" at a local middle school (I'm not a masochist, I had my own reasons for wanting to do this.) The staff member just called me and told me that I'm up for it, in a week. Here are the parameters:
  • I have 30 minutes. 
  • It's 10-20 middle schoolers. 
  • It's a classroom, not a laboratory. 
It's been suggested to me that I do a demonstration and I give a brief presentation on my career path. I'd like to do both, obviously, with 10-15 minutes saved up for an ask-me-anything time period. 

I would like to do a chemistry experiment that's short, exciting and demonstrative of reaction chemistry. Unfortunately, I don't have the resources to provide all the PPE safety/gear needed for a real demonstration (like thermite or something.) I'm going to cover my career path and be painfully honest about my circumstances. 

So, readers, any suggestions?

UPDATE: My goodness, so many suggestions -- thank you so much! 

27 comments:

  1. And, no, I'm not going to burden them with the unemployment rate of mid-career chemists. I'm probably going to say, "If you just want lots of money, chemistry is not the career for you."

    ReplyDelete
  2. When short of time, do the sulfuric acid / glucose snake demo. Always a crowd pleaser, and cheap / easily explained.

    ReplyDelete
  3. I've got a whole book of demos at home targeted at middle/high school students, many of which don't require much PPE for the observers. I will try and find some more specifics later. Generally, gooey things they can touch and play with go over well, and there's a few options that don't make too much mess.

    Also, explaining how toys work can go over pretty well (http://www.thinkgeek.com/product/e6d1/ or http://www.thinkgeek.com/product/c393/ )

    And you've probably found this, but it may be a good source of inspiration: http://www.reddit.com/r/chemicalreactiongifs/

    ReplyDelete
  4. They did the same in my school when long time ago. I can still remember that the ballon that was self inflating (sodium bicarbonate + vinegar) and the solution that was changing color (acid/base indicator) were a kind of magic for me. Also you can try some kind of chemical clock. These are completely safe even without any protections.
    My main concern is that I'm talking of c.a. 20 years ago. Nowadays the kids attention and the definition of "magic" can be different.

    ReplyDelete
  5. I generally like to tell these types of audiences that a lot of my lab work involves making molecules and purifying them. The variety comes in all of the different things you can make, ways for making them, and methods for purifying/separating.

    One of my favorite simple demos for illustrating this concept is the PbI2 precipitation. You add a solution of lead nitrate to a solution of potassium iodide. The two clear solutions produce a bright yellow mixture on contact. It is not immediately obvious that you've produced a solid, but you can then do a simple filtration to show how to isolate the product.

    Not sexy, but definitely simple, and it gives you a springboard to talk about reactions, synthesis, etc. I also like separating dyes with paper chromatography and bringing along a column to show how it's done on a bigger scale.

    ReplyDelete
  6. Ooh, there's always the phenolphthalein / soda straw trick (which takes almost no effort to set up). Kids blow air from their lungs (CO2-enriched) into a solution until enough carbonic acid forms to turn the indicator. Easy, no mess.

    ReplyDelete
  7. Anything with chemiluminescence kids seem to like.

    ReplyDelete
  8. I always thought the oscillating BZ reaction was pretty neat.

    ReplyDelete
  9. Tollen's Test - Alot of different color changes with a grand finale of a mirrored flask!

    ReplyDelete
    Replies
    1. Tell them you're going to synthesize a monkey in a bottle. Hand it to someone when it's done and say, "See the monkey in the bottle?"

      Delete
  10. Lots of great suggestions. I like the clock reaction. I think there's an easy/safe trick of making silly putty. I'm not sure of the PPE requirements.

    ReplyDelete
  11. The NSF center CENTC did an outreach project on energy that was really well received. I participated and also went to another school and gave a talk on energy that went well (both of these were several years ago now... 2009 I think). I would suggest talking about chemistry and energy, with an emphasis on oil, CO2, and renewable energy? Tell them about how chemistry can be used to solve the energy problem.

    ReplyDelete
  12. Some of these look pretty good:
    http://www.neatorama.com/2009/11/04/top-10-mad-science-worthy-chemistry-experiments/
    No. 6 would be my favorite.
    Failing that, there's always neat stuff you can do with dry ice.
    Then you can tell them all to become merchant bankers.

    ReplyDelete
  13. In my teacher training year I did a demonstration where I melted some candle wax in a crucible and set fire to it, simulating a chip pan fire. I then showed the class how NOT to put out a chip pan fire, by adding a couple of drops of water (which turned it into a flame-thrower - make sure they're standing well back!)
    It got quite a reaction from them, and hopefully instilled a useful safety lesson.

    ReplyDelete
  14. I recently volunteered for elementary school students, so unless students completely change in middle school, this might be useful:

    1) Kids are still very easily impressed. Don't think you have to do some laser show worthy of Disneyland to get their attention. They will consider the demo a treat and a nice break from books. If all you have is an egg and a glass of water, they will be all in.

    2) They will look at you not as "Chemistry Expert" but "Science Expert", so prepare to get all sorts of questions from everything ranging from volcanoes to solar systems.

    3) In the "things have changed since my day" category, your room may have an ultra-sensitive smoke detector. So anything involving lighting a match needs to be taken outside.

    ReplyDelete
    Replies
    1. Thank you -- this advice is really helpful.

      Delete
  15. stewie griffin:
    Make nylon 6,6. Very easy and very cool - you pull a solid string out of a beaker filled with two different liquid layers!

    ReplyDelete
  16. I was also going to suggest the nylon experiment. its quick and gets tangible results.

    ReplyDelete
  17. Believe me, the juice from a red cabbage at different pHs (basically strong and weak acid and base) will give some awesome colour changes including to a bluey-purple. Get the class to guess the colour as you change the pH. Very safe, and no issues with smoke detectors.

    ReplyDelete
  18. aluminum or magnesium powder + KMnO4 powder as oxidizer = flash . Mixed freshly only before the demonstration. Addition of a small quantity of sulfur powder into the mix makes the ignition easier. (You can never go wrong with blinding the kids and at the same time painting them brown and pink with permanganate)

    ReplyDelete
  19. They also love liquid nitrogen, freezing flowers, bananas, deflating balloons, all the usual tricks.

    ReplyDelete
  20. Extraction of DNA from fruit (strawberries or kiwi fruit) can be fairly impressive and is doable with stuff you could find in an average kitchen.

    ReplyDelete
  21. I have down the pH rainbow experiment for 5th graders. Typically I set up the base solution with indicator in my lab, in a Nalgene bottle. Take the dry ice and a large E-flask. I also bring a box of gloves and some goggles, and discuss safety. I print out a "notebook page" for each student to write down their observations. Discuss the importance of observation. Slowly add the dry ice with swirling, while discussing pH, and foods that are acidic/basic. Kids love the "smoke" and the nice color changes. I've done this one may times over the years, and it always goes over well. The luminol experiment is more work to set up, but it always gets a great response too.

    Kids are natural experimentalists - I agree with the above commenter that you will be there as not just a Chemist, but as a Science expert - they ask all kinds of questions! If you smile a lot, and talk about how interesting the universe is, well, you'll do great!

    ReplyDelete
  22. @CJ: Dude, jump on the CSI bandwagon and show fingerprint (the amino acids) detection with ninhydrin.

    Or, have the kids make their own instant cold packs. You're in an agricultural part of the country, right? So getting ammonium nitrate and some zip-lock bags shouldn't raise any red flags.

    ReplyDelete
  23. Ill say it again CJ, blow something up. (10th grade chem, blew up a pumpkin before Halloween, just behind a blast shield in the classroom, yeah, so now Im a chemist I guess...)

    ReplyDelete
  24. The reaction of lead nitrate and potassium iodide is shown at 1:20 and 2:06 in the “Chemmin’ It Up Tik Tik Chemistry” video. http://www.youtube.com/watch?v=FLWEnLSAbJg. Chalk chromatography is easy to perform. http://www.chymist.com/chalk%20chromatography.pdf

    ReplyDelete
  25. It's probably too late, but this just came out of the gutenberg project and seems from an old version of the RSC Xmas lecture.

    http://www.gutenberg.org/files/41839/41839-h/41839-h.htm

    "THE BOY'S PLAYBOOK OF SCIENCE: INCLUDING THE
    Various Manipulations and Arrangements
    OF CHEMICAL AND PHILOSOPHICAL APPARATUS REQUIRED FOR THE SUCCESSFUL PERFORMANCE OF SCIENTIFIC EXPERIMENTS.

    IN ILLUSTRATION OF THE ELEMENTARY BRANCHES OF CHEMISTRY AND NATURAL PHILOSOPHY.

    BY
    JOHN HENRY PEPPER, F.C.S., A. INST. C.E.; LATE PROFESSOR OF CHEMISTRY AT THE ROYAL POLYTECHNIC, ETC. ETC. AUTHOR OF "THE PLAYBOOK OF METALS."

    a quick look shows some parlour tricks I hadn't seen before, but you may want to rephrase the 1869 explanations in view of recent theory.

    There is also
    http://sciencedemonstrations.fas.harvard.edu/icb/icb.do
    which for the undergrad kiddies who parked their car in the yard. This covers basics physics and such as well and should reflect current thinking in safety & legal liability.

    ReplyDelete