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“Why do I have a garbage can full of liquid nitrogen? Because I’m a chemist,” Doug Mulford, director of undergraduate education for Emory’s Department of Chemistry, told a crowd of enthralled children and adults.
Decked out in safety glasses and a red lab coat printed with flames, Mulford conducted a ribbon immolation ceremony on Saturday, to officially open Emory’s Sanford S. Atwood Chemistry Center addition. The crowd gasped and cheered as Mulford ignited a thermite reaction in the courtyard, a pyrotechnic mixture of aluminum and iron oxide. The reaction shot off sparks and smoking-hot globules of molten iron to sever the ceremonial ribbon.
Rain did not dampen anyone’s enthusiasm for the grand opening, which included fun science demonstrations by students from chemistry, biology and physics.
In fact, chemists love water droplets and clouds. Graduate students from Emory’s Pi Alpha Chemical Society showed how to make both, using liquid nitrogen.
“We’re pouring really hot water into really cold liquid nitrogen, causing it to expand into a plume of air that comes up as a cloud,” explained Daniel Collins-Wildman, who braved nature’s drizzle in the courtyard along with fellow graduate student Amanda Dermer.
In fact, Collins-Wildman said, the liquid nitrogen is so cold (77 Kelvin) that ice particles form in the cloud, creating what is known as a nucleation site where water drops can form.
“I conducted an experiment with this by accident once, when I was making macaroni and cheese,” he said. He brought the water to a roiling boil. As usual, bubbles formed along the top of the water, where the temperature is slightly cooler and the pot’s irregular surface forms nucleation sites. Then the power went out. The result was a massive homogeneous nucleation of vapor bubbles and a phase explosion.
“The water was still hot, but the bubbles along the periphery of the pot weren’t there,” Collins-Wildman said. “Then I heard this weird sound. All those little bubbles had turned into one huge bubble that came to the surface with a BLURP!”
Related:
Chemistry Center turns up the heat for grand opening
from eScienceCommons http://ift.tt/1FDGRf4
Click here if video does not appear on screen.
“Why do I have a garbage can full of liquid nitrogen? Because I’m a chemist,” Doug Mulford, director of undergraduate education for Emory’s Department of Chemistry, told a crowd of enthralled children and adults.
Decked out in safety glasses and a red lab coat printed with flames, Mulford conducted a ribbon immolation ceremony on Saturday, to officially open Emory’s Sanford S. Atwood Chemistry Center addition. The crowd gasped and cheered as Mulford ignited a thermite reaction in the courtyard, a pyrotechnic mixture of aluminum and iron oxide. The reaction shot off sparks and smoking-hot globules of molten iron to sever the ceremonial ribbon.
Rain did not dampen anyone’s enthusiasm for the grand opening, which included fun science demonstrations by students from chemistry, biology and physics.
In fact, chemists love water droplets and clouds. Graduate students from Emory’s Pi Alpha Chemical Society showed how to make both, using liquid nitrogen.
“We’re pouring really hot water into really cold liquid nitrogen, causing it to expand into a plume of air that comes up as a cloud,” explained Daniel Collins-Wildman, who braved nature’s drizzle in the courtyard along with fellow graduate student Amanda Dermer.
In fact, Collins-Wildman said, the liquid nitrogen is so cold (77 Kelvin) that ice particles form in the cloud, creating what is known as a nucleation site where water drops can form.
“I conducted an experiment with this by accident once, when I was making macaroni and cheese,” he said. He brought the water to a roiling boil. As usual, bubbles formed along the top of the water, where the temperature is slightly cooler and the pot’s irregular surface forms nucleation sites. Then the power went out. The result was a massive homogeneous nucleation of vapor bubbles and a phase explosion.
“The water was still hot, but the bubbles along the periphery of the pot weren’t there,” Collins-Wildman said. “Then I heard this weird sound. All those little bubbles had turned into one huge bubble that came to the surface with a BLURP!”
Related:
Chemistry Center turns up the heat for grand opening
from eScienceCommons http://ift.tt/1FDGRf4
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