Thuvan N. Piehler usually spends her days working with explosives at Aberdeen Proving Ground. Yesterday, she helped young students in southeastern Baltimore County understand chemistry -- using balloons, crackers and glue.
Piehler was among five chemists from the U.S. Army Research Laboratory at Aberdeen Proving Ground who designed hands-on experiments for Colgate Elementary School's fourth-graders to get them excited about chemistry.
Sandra Young, a materials engineer, told the children that chemicals are in everything that they can see, smell and touch.
"Science is all around us," she said.
Kirstan Baxter, 9, said the presentation was "cool."
"I think that if I became a scientist, I would be good at it because now I know everything is made of chemicals," she said.
The scientists from Aberdeen Proving Ground presented their program as part of the American Chemical Society's National Chemistry Week.
In the children's first experiment, they smelled the outside of inflated balloons. The chemists had placed peppermint oil inside the balloons the night before. They used the activity to demonstrate diffusion, explaining that the molecules of the oil had seeped through the latex's microscopic pores, allowing the kids to detect the scent on the outside of the balloons.
During the second experiment, students were asked to make three marks on white paper using red grease pencils. They then asked students to use cotton swabs to place water, acetone and soap on the three marks. Most students agreed that the acetone erased the mark best. The scientists related the activity to everyday life, explaining how dry cleaners use acetone or similar chemicals to take grease and other stains out of clothing, and how lipsticks tend to be greasy so that water won't easily erase them.
A third experiment showed the students how iodine identifies starch, in this case in a cracker. Finally, the students mixed polyvinyl alcohol, a milky substance found in white glue, with borax, found in cleaning solutions. The result was a gooey substance.
Oohs and ahhs and requests to take the result home filled the cafeteria. The scientists used this activity to demonstrate how molecules can bind to change the form of a substance.
"I learned some new things," said 8-year-old Victoria Melgar. "And if I were a scientist, I could teach other kids about it."
The scientists also got something out of the event.
"All of us really believe in science education," Young said. "It's important for kids to actually meet scientists."
"This allows them to learn about what we do. They also see that there are all kinds of scientists, women and people of different backgrounds."