ScienceMakers Toolkit Manual - The History Makers

Chemistry
9. If you were a chemist, what kinds of questions would you study?
10. Dr. Antoine did much of his work in fuel research for jet engines. He talks about the effi ciency of a fuel.
What do you think he means by this? Can you think of other places where you have heard about fuel
effi ciency? How does fuel effi ciency affect your life? How do you think it will affect your life in ten
years? What kinds of things could you study to work in that fi eld? (See Clip #4)
11. Dr. Antoine talks about his program to work with alternate fuel sources. What fuel sources was he
studying? Why was this program abandoned? Do you think this program would be helpful now? Why?
What kinds of alternate fuel sources do we use today? Can you think of anything else we could maybe
use as a fuel source? How would you harness that energy? (See Clip #5)
12. Dr. Antoine talks about the mix of hydrogen and carbon. What is this called? Where do we get this mix
today? He also began working with a mixture of carbon and something else. What was it? Did his
experiment work? What did he fi nd as his results? Why was the program fi nally abandoned?
(See Clip #5)
Experiment – Mentos Rocket
Chances are you’ve heard of this experiment, so here is a chance to do it for yourself. In keeping with Dr. Antoine’s
work with jet propulsion and rocket fuel, you will be doing the rocket version of this experiment rather
than the more-well-known fountain version. Using the instructions below, from http://wtwii.fi les.wordpress.
com, make a rocket out of a Diet Coke two liter bottle and some Mentos.
How Does It Work? From www.eepybird.com:
There has been a lot of discussion online about why Diet Coke and Mentos make such an interesting combination.
What everyone can agree on is that the carbon dioxide that has been compressed into the soda escapes so
rapidly that the pressure pushes the soda out of the bottle. It’s like shaking a bottle before you open it, but even
more dramatic.
These chemists are saying that the primary cause is physical, not chemical. Their explanation: nucleation sites.
If you have a liquid that is supersaturated with gas (like soda, which is pumped full of carbon dioxide), a nucleation
site is a place where the gas is able to form bubbles. Nucleation sites can be scratches on a surface or
specks of dust – anywhere that you have a high surface area in a very small volume. That’s where bubbles can
form.
Mentos seem to be loaded with nucleation sites. In other words, there are so many microscopic nooks and
crannies on the surface of a Mento that an incredible number of bubbles will form when you drop it in a bottle
of soda. Since the Mentos are also heavy enough to sink, they react with the soda all the way to the bottom.
The escaping bubbles quickly turn into raging foam, and the pressure builds dramatically. Before you know it,
you’ve got a big geyser happening!
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