 | Students at North Dundas District High School (NDDHS) celebrated Halloween Monday by witnessing flames erupting from a jack-o-lantern, smoke billowing from witch's brew, and dire warnings mysteriously appearing on the walls of their classroom - all in the name of science.
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Chesterville - Nov. 1, 2011 - Students at North Dundas District High School (NDDHS) celebrated Halloween Monday by witnessing flames erupting from a jack-o-lantern, smoke billowing from witch's brew, and dire warnings mysteriously appearing on the walls of their classroom - all in the name of science.
Nearly 200 students in Grade 7, and Grades 9-12 were thrilled by A Halloween Story, a 20-minute dramatic presentation designed to entertain and inspire an interest in chemistry through wondrous special effects that relate to the curriculum. The idea behind the narrated show was to demonstrate that science can be fun, said NDDHS science teacher Jennifer Onstein, an organizer of the event.
"We wanted to increase interest in science in a fun way," said Onstein. "It's really important for kids to see science in action. Rather than just read about it in books, it's much more fun for students to see chemical reactions in person. And we showed them in the context of a Halloween story, which makes it even more special for them."
The dramatic presentation, held in a chemistry lab at the school, told the tale of Alex and Walker, two trick-or-treaters who approach the old Guenther mansion - home of the much feared Old Woman Guenther. While Walker magically receives a giant version of his favourite candy bar, Alex is burdened with a mysterious bottle. Once she rubs it, she releases a genie who curses her - warning her she must solve his riddle or die within four hours.
Over the course of the play, Alex passes by a jack-o-lantern that shoots flames, a flurry of bats, a witch's spell book on which flames magically dance, and a sign on which blood-red words such as Beware and Turn Back magically appear and disappear.
All of the entertainment actually showed scientific concepts that teachers would demonstrate in their classrooms, said Onstein.
The sign used in the play showed students about the chemical reaction between acids and bases. The sign was initially treated with an acid-based indicator known as phenolpthalein. Onstein used the clear liquid to write Beware on the sign. During the presentation, a student special effects crew sprayed the sign with a base. The resulting reaction turned the mixture blood red - causing the invisible warning to magically appear.
The flames on the spell book were a carefully planned effect designed to demonstrate a scientific principle know as the combustion principle. A portion of the book was hollowed out to leave two cavities. A wick and a flint were inserted into both, before the cavities were soaked with lighter fluid. The narrator holding the spell book needed merely to strike the flint and ignite the wick. She then closed the book part way to spread the fire to the other side, and then closed it fully to kill the flames. The trick demonstrated a key element of the combustion principle, the requirement for oxygen.
The flame-shooting jack-o-lantern was another effect arranged to demonstrate combustion. A teaspoon of lycopodium powder was placed in a small funnel attached to a rubber hose and the funnel was positioned over a lit Bunsen burner placed inside the jack-o-lantern. When a member of the special effects crew blew into the hose, it blew powder over the flame, causing the powder to ignite and carry the flame in the direction that the powder was blown. The experiment demonstrated how a combustible material, spread over a large area and mixed with oxygen before ignition, can lead to an accelerated combustion.
Students such as Cristian Vogrig, a Grade 7 student at the school, said the demonstration will inspire him to take science.
"All the features and special effects were amazing," he said. "It's cool to start mixing stuff together and seeing fire (shoot out). I'm really interested now."
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