Infrared Image of Warm-Blooded and Cold-Blooded Animals

This FLIR image was taken of warm-blooded people and a pygmy African hedgehog, as well as a cold-blooded corn snake.

Vernier Oxygen and Carbon Dioxide Sensors Around a Campfire

I slowly walked around the glowing coals of a campfire tonight while holding Vernier oxygen and carbon dioxide sensors at about hip level.  The highs in the carbon dioxide readings correspond to lows in the oxygen readings, and these highs and lows correspond to when I was roughly east of the fire.  Though the wind was almost calm, it appears to me that the "smoke" from the fire was blowing toward the east.   I think under much more controlled circumstances this could lead to classroom/laboratory exercises in mapping plumes of gases from point sources.

Heat Camera on Glow Sticks

I used an FLIR camera from a local museum to capture these images of hands holding glow sticks.  The images show how the chemiluminescence of the sticks is considered to be a relatively cold source of light. The hands glow more brightly in the IR image than do the sticks!

Softening Point of 2-Liter PET Soda Bottles

When exothermic demonstrations are performed using 2 L polyethylene terephthalate (PET) soda bottles, the bottles sometimes soften and shrink.  A great example of an exothermic reaction that can do this to PET bottles is the catalytic decomposition of 30% hydrogen peroxide.  Wikipedia has mentioned that the glass transition of PET is about 70 C, so we set out to check to see if that corresponded to the softening point of the PET bottles.  We heated a large kettle of water to various temperatures with a stove, checking the water temperature with a Vernier temperature probe.  At selected temperatures, we placed a 2 L PET bottle nearly completely into the water (with its opening above water and the interior NOT flooded with water) for one minute.  The results are shown in the picture below.  At 65 C the bottle is unchanged, but at roughly 70 C and above, the bottle deforms.  The extent of the bottle deformation seems to increase as the temperature increases. Thanks to Kristine Campbell for assistance with the experiment.