By Tim Krohn
ST PETER — In the world of science and children, you can never, ever go wrong with exploding Gummi Bears.
“That one’s my favorite,” said Maren Schettler, a St. Peter first-grader. “We melt sugar and put a Gummi Bear in it and it blasts it out.”
Technically, said Ryan Espy, president of the Gustavus chemistry club, which helped sponsor the Science on Saturday event for area kids, it wasn’t sugar that was melted.
Potassium chlorate looks like sugar and is a strong oxidizing agent that reacts violently with sugar, like the sugar-ladened Gummi Bears.
Although the student-run chemistry, biology and physics clubs change up the experiments each year to provide something new for returning students, there are old-time favorites that always remain. One is the liquid nitrogen added to the cream and sugar mixture, providing a nice fog rolling out of a big bowl. Better yet, it quickly turns the mixture into tasty ice cream for the 130 1st-6th grade students attending the event at Nobel Hall on the Gustavus campus.
Nick Hefty and David Guptill, senior chemistry majors, were wowing students in one classroom by pouring clear liquids together, which then turned from dark blue to yellow and back several times.
“So, this is what we call magic,” Hefty told the awestruck kids. “No, seriously, it’s science,” he says, as he goes on to explain how the hydrogen peroxide mixed with the iodine caused the reaction.
“You have to do something that sparks their interest, something they will remember,” Hefty said of doing the experiments. “It has to change color or explode.”
While many of the experiments had a big wow factor, many of the more cerebral experiments were just as interesting for the kids.
In the biology room, pre-med student Ashley Baumann was helping kids plant seeds they would take home, look at the pelts of various animals and peer into microscopes.
“There’s mammal stomach in here,” Schettler, the first-grader, said as she looked in the microscope. “It looks orangey and yellow.”
Baumann said the students, from dozens of area schools, show a true interest in science.
“They have a lot of fun and they ask great questions. They want to know how you tell if a turtle is male or female or what eats crawfish,” Baumann said. “It makes me go back and start wondering about those things.”
Le Sueur 5th-grader Laura Schwartz admitted science isn’t her favorite subject in school, but she liked her second year at the Science on Saturday event.
“It’s fun. I like the greenhouse the best. Looking at the cactuses.”