High School Biology-Chemistry SMILE Meeting
28 September 2004
Notes Prepared by Porter Johnson
- Write-ups for academic year SMILE
meetings for the current semester may be found at http://www.iit.edu/~johnsonp/acysmile.html,
and write-ups from previous semesters are permanently located at biweekly.htm.
- Hang tags, which permit parking in the IIT lot on the
Northeast corner of 31st Street and State Street, were passed out
at the meeting. These hang tags should be hung from the rear view
mirror of your vehicle, so that the writing is visible from the
outside. They are valid only on Tuesday afternoons after 4 pm,
from now until the end of the Spring semester 2005.
- Carol Giles [Collins HS] called attention to her newly
published book, Gifted
and Gone: Proverbs, Quotations, Sayings and More. The book is
described as " A collection of humorous and thought-provoking quotes
from all aspects of
human life." It is available from
For details see this
Chris Etapa [Gunsaulus
son bought an "ecosphere" for her for about $20 (oddly, at an
electronics store). It is a glass globe
that is sealed. It is 3-4 inches (8-10 cm) in
diameter. It contains brine shrimp (5) and algae and about 6
snails. The system is self contained and self
sustaining. It is about 3/4 filled with water. The algae make oxygen
respiration of the snails and shrimp which make CO2
for the algae.
The algae presumably make biomass to support
the growth of the shrimp and snails. Enough nutrients (presumably for
algal growth) are included in the
solution to support at least 2 years of sustainability. We enjoyed
passing the ecosphere around and
examining it close up. Very interesting, Chris!
Terry Donatello [ST Edwards School, Elmwood
and how to show some things about atoms, even though you can't see atoms
sense a version of the Rutherford gold foil experiment [http://www.chemsoc.org/timeline/pages/1911.html]
) We all welcomed Terry back with great enthusiasm!
- Terry distributed clay balls about 2 inches (5 cm)
in diameter, along with toothpicks. Toothpicks were used to probe into
balls inside each of which Terry had hidden something. Using
the toothpick probe and sticking it
into the clay balls, we tried to infer what is inside without actually
it. Strategies included sticking
numerous toothpicks into the clay balls from all different directions
variation in the depth of sticking. The
more toothpicks, the better, and some groups used up to 20 or so
to complete their probing.
With regard to accuracy, our
results were mixed! Objects included a wing-nut, a plastic bottle cap,
and half-circle bracket.
- Terry had taken a shoe box and hidden something inside.
She cut out
the ends and replaced them with
flaps of construction paper that had been cut into strips to allow a
go in and out of the shoe box when rolled inside, without allowing us
what is inside. Also, the marble would ricochet backwards because of
inside the box. Again, this is a nice model of the Rutherford
- Terry put 4 steel balls or rubber balls in an aluminum pie
indentations in the bottom of the pan to hold the balls stationary and
marbles down a ramp made from a 1 foot ruler to hit the balls. We tried
to do a
lot more similar permutations of this technique, using rubber and steel
as well as marbles as targets (in the pie pan) and as projectiles
the ramp). We tried to see the results with a certain type of
striking a given target at a certain speed and location, etc.
These were good
models of the Rutherford experiment! Thanks, Terry.
Ken Schug [IIT Chemistry] Ken's "Chemistry Road
Wonderful phenomenological chemistry, Ken!
Roster for Future Meetings
- First, Ken showed two 10 oz (300 ml) pop
bottles that were both about 2/3 filled with a reddish
They looked the same, but were they? How could we decide this?
Density? pH? Smell? Open the bottles and mix
them together was Ken's idea. When we
mixed them, they appeared to be the same, as there was no separation of
into different layers, etc. Ken confirmed that they were the
same, a solution
of CoCl2. The color comes from the Co2+
We investigated further. One bottle was
warmed (in a warm water bath) and the other was chilled (in an ice
The chilled one became redder, but the warmed
bottle turned blue! Co2+ ions hydrated
with 6 waters (pink) and (CoCl4)2-
(blue) were in equilibrium with each other,
and this equilibrium point was shifted by the temperature. The
different colors of the two species are due to the different
electron energy levels between the two.
A Co2+ ion in "cobalt glass" that is
structured similarly to the (CoCl4)2-
gives cobalt glass
its distinctive blue color.
- Ken suggested that flour could be a renewable fuel! He
poured out some flour (the flour had been pre-dried in an oven)
into a metal dish and tried to light it with a match (without success).
He then poured out some flour into a small
plastic funnel attached to about 2 feet of rubber tubing. With the
lights out, Ken blew gently on the
tubing to make an aerosol of the flour above the funnel while he put a
match in. We got a great flame! The greater oxygen to flour
ratio of the
aerosol allowed the flour to burn. This is the same principle
leads to grain elevator explosions!
- Into one baggie (sealable with a tie) Ken put hydrogen
peroxide solution and dry
yeast. Peroxidase in the yeast converts
the peroxide into water and oxygen; the oxygen collects in the baggie
is tied off. We could see the results of the reaction as a foaming (the
reaction gave off heat as well, and Ken could feel the baggie
get warmer). A baggie just filled with air was pierced
with a lighted cigarette, but nothing happened.
The yeast-peroxide baggie pierced the same way resulted in a
bright glow when the cigarette pierced the baggie; this was due to the
concentration of oxygen inside this baggie than in ordinary air, which
supported a greater amount of combustion.
| Oct 12
| Oct 26
||Wanda Pitts, Barbara Lorde
| Nov 09
|| - x -
| Nov 23
| Dec 07
| Dec 14
|| - x -
Notes taken by Benjamin Stark.