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Hot and Cold Equilibrium—LeChâtelier’s Principle—Chemical Demonstration Kit

By: Walter Rohr, Retired , Eastchester High School, Eastchester, NY

Item #: AP5938

Price: $20.95

The Hot and Cold Equilibrium LeChâtelier’s Principle Chemical Demonstration Kit is amazingly simple, but intriguing. Challenge students to explain the phenomenon observed when the tubes of violet solution are reversed in hot and cold water baths.

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This item can only be shipped to schools, museums and science centers

Product Details

Challenge students to explain the phenomenon observed in this amazingly simple but intriguing demonstration. Pour some violet colored solution into three different test tubes. Place one tube in cold water—the solution turns pink, from the bottom up. Place another tube in hot water—the solution turns a deep blue from the top down. Leave the third tube at room temperature—the solution remains violet. Watch what happens when the tubes are reversed in the hot and cold water baths. Teacher Demonstration Notes included.  

Concepts: Equilibrium, LeChâtelier’s Principle, density, absorption/transmission.
Time Required: 20 minutes
Materials Provided: Cobalt chloride/alcohol solution, test tubes, and stoppers.