Photo Index - "Cold, Colder, Coldest"
On Wednesday, 03 March 2004, Dr. David Venezky, retired chemist, U.S. Naval Research Laboratory,
Washington, D.C., visited Sandburg MS Grade 8 Physical Science classes
for a fun-filled day of safe demonstrations of extremely cold
materials. Our sincere thanks to Dr. Venezky--at CSMS, we appreciate
your spirit of volunteerism and willingness to share your expertise
and enthusiasm for hands-on chemistry! Thanks
to the following Sandburg Grade 8 Physical Science teachers for
providing the opportunity for students in their classes to participate
in the special event: Ms. Langer; Ms. Wallace; Mr. Clemons; and Mr.
Sanford.
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 1/2-size | full-size | info At average temperatures on the Earth's surface, water ice (solid H2O) melts, changing phase to become liquid water. |
 1/2-size | full-size | info In contrast, "dry ice" (solid CO2) doesn't melt, it sublimes into CO2 gas. Ms. Baena shown in background. |
 1/2-size | full-size | info Goggles, gloves, & tongs used for safety. Extremely cold materials can cause severe burns & instant frostbite. |
 1/2-size | full-size | info Comparing freezing & boiling points of H2O, CO2, and N2. |
 1/2-size | full-size | info "Dry ice" is ideal to use for shipping perishable items. |
 1/2-size | full-size | info Pouring liquid nitrogen (N2) from a "Dewar" flask. |
 1/2-size | full-size | info Ms. Langer & Dr. Venezky. Pink balloon filled with N2 gas; green balloon filled with CO2 gas. |
 1/2-size | full-size | info Blowing bubbles... |
 1/2-size | full-size | info ...into a tank of CO2. |
Related Resources
- Dr. Venezky's list of provisions for "Cold, Colder, Coldest" demonstrations.
- Bubble Suspension - Soap bubbles float on a cushion of carbon dioxide gas, from Exploratorium Science Snacks. See also, the Floating Bubble Demo.
- QuickTime movies from the NCSU Physics DemoRoom: Smashing Racquet Ball; Balloon in Liquid Nitrogen; Burst a Balloon; and Exploding Racquetball Can.
- Heat Demonstrations, from Physics Demonstrations, A Sourcebook for Teachers of Physics, by Julien C. Sprott.
Photographs courtesy Walter Sanford, Teacher, SMS Physical Science & FCPS Planetarium.
Thumbnail images prepared using photoweb by Phil Wherry & Eric Johnston.
More Photos... | Carl Sandburg Middle School | Fairfax County Public Schools