Vomiting pumpkins, purple flames and color-changing liquids are just some of the attractions during today’s free, kid-friendly “Magic of Chemistry” show at the University of Colorado at Boulder.
The show is part CU Wizards, a monthly program designed to introduce school-age kids to the wonder of science.
Scientists from various disciplines will be on hand for the show. Veronica Bierbaum, for instance, will demonstrate how chemical reactions produce seemingly magical visual effects.
“It’s very dramatic,” Bierbaum, a professor of chemistry and biochemistry at CU-Boulder, says of the demonstration. “We use a combination of fascinating reactions and explanations to show how chemistry seems magical, but it is all very well understood.”
To produce a vomiting pumpkins, carved jack-o’-lanterns are filled with a combination of soap, hydrogen peroxide and a catalyst. The chemical reaction makes the soap bubble and foam, and then spew forth from the mouth of the pumpkin.
During another demonstration, liquids are combined in a beaker so that the color oscillates between deep blue and bright orange. To explain the complex chemistry to young students, Bierbaum describes it as “a tug of war between the chemicals.”
Certain chemical properties have long offered amusement as parlor tricks. Like the use of “Prince Rupert’s Drops,” tadpole-shaped pieces of glass that provided puzzling entertainment during 17th- and 18th-century high-society soirees.
“They are incredibly strong,” Bierbaum says. The glass droplets can withstand the blow of a hammer if hit on the larger, round end but “crumble into sand” if they’re so much as chipped at the smaller, tail end.
The CU Wizards outreach program draws on these kinds of science-backed tricks to seduce youngsters to the discipline. Now in its 34th season, the program offers monthly classes from September through June in partnership with CU Science Discovery.
David Nesbitt, a physicist with the National Institute of Standards and Technology and an adjoint professor in CU’s physics, chemistry, and biochemistry departments, has served as the director and “Chief Wizard” for the past 16 years.
“The program started out as a fairly modest adventure,” Nesbitt says. “But now over 35 faculty members are Wizard presenters.”
Professors from departments as varied as math, psychology, geoscience and astrology volunteer as Wizards and present these free classes to groups of 200 or more kids and parents. Nesbitt says the programs are designed to be fun and energetic, and kids are encouraged to ask questions and volunteer.
Ideally, the program sparks in its participants a lifelong interest in the sciences.
“We had a special 30th-anniversary program a few years back,” Nesbitt recalls. “She found some young scientists who went through the Wizards program and later came to CU and graduated.
“We love to send these students off to do great things in the wider world,” Nesbitt says.
Getting kids into the laboratory
CU Wizards present “The Magic of Chemistry”
When: Today at 9:30 a.m.
When: University of Colorado at Boulder, the Cristol Chemistry Building, Room 140
Information: For more about the Wizards program and upcoming science shows, call 303-492-5011 or visit
