Is fire a solid, a liquid, or a gas? – TED Ed by Elizabeth Cox

Sitting around a campfire, you can feel its heat, smell the woody smoke, and hear it crackle. If you get too close, it burns your eyes and stings your nostrils. You could stare at the bright flames forever as they twist and flicker in endless incarnations… But what exactly are you looking at? Elizabeth Cox illuminates the science behind fire. Continue reading

Cornstarch & Water – Explained by Physicists

Heinrich Jaeger, William J. Friedman and Alicia Townsend Professor in Physics, and Scott Waitukaitis, a graduate student in the Physics department, have published a report in the July 12 issue of Nature on the process of impact-activated solidification that occurs when compressive forces are applied to fluid-grain suspensions. The two researchers conduct experiments with a mixture of cornstarch and water that is classified as a non-Newtonian liquid. Their work examines the strange behavior of the cornstarch-water liquid, which instantly changes into a solid within the area of impact. The behavior of non-Newtonian liquids has puzzled scientists for decades, and Waitukaitis and Jaeger’s report sheds new light on this longstanding problem in suspension science.

Solid Nitrogen

Published on Dec 18, 2012

Amazing! Place liquid nitrogen in a vacuum chamber and observe frozen nitrogen “ice.”

This video is part of the Flinn Scientific Best Practices for Teaching Chemistry Video Series, a collection of over 125 hours of free professional development training for chemistry teachers –http://elearning.flinnsci.com

ATTENTION: This demonstration is intended for and should only be performed by certified science instructors in a safe laboratory/classroom setting.

Don’t Keep Your Hot Water Bottled Up

Two thermometers

Hot water rises because its molecules are moving rapidly as they expand the water.  Hot water is less dense, therefore, the same amount of water takes up the larger space. Hot water rises above the colder denser water.  The resulting movement is called convection.  The flowing displacement of a mass of cold fluid under large amounts of hotter fluid is the same phenomena seen with weather patterns where cold higher pressure air displaces and pushes up the hotter air. Hot air balloons also take advantage of this squeezing action.

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