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Flinn Lab Activities and Demonstrations
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Hot and Cold Equilibrium— Le Chatelier’s Principle— Chemical Demonstration Kit AP5938
Chemical Equilibrium—Demonstration Kits,
continued
Hot and Cold Equilibrium—
Le Chatelier’s Principle—
Chemical Demonstration Kit
By: Walter Rohr, Retired, Eastchester High School, Eastchester, NY Challenge students to explain the phenomenon observed in this amaz- ingly 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. Demonstration Notes included.
Concepts: Equilibrium, Le Chatelier’s Principle, density, absorption/ transmission.
Time Required: 20 minutes
Materials Provided: Cobalt chloride/alcohol solution, test tubes, and stoppers.
Pink and Blue—A Colorful Chemical Balancing Act— Chemical Demonstration Kit By: Jim and Julie Ealy, Retired
The Peddie School, Hightstown, NJ
Demonstrate the power of balance in a reversible chemical reaction with this updated version of a classic demonstration! A solution of cobalt chloride turns from pink to blue and back again in a series of transformations as the concentrations of reactants and products and the temperature are changed. Students observe how a reaction at equi- librium responds immediately to conditions that upset its chemical balance. As students visualize the dynamic nature of equilibrium, they are able to explain in their own words how Le Chatelier’s Principle works and why it makes good chemical sense. Whether you want to show only qualitative effects or to develop a more quantitative treat- ment with equilibrium constant examples, this demonstration is perfect. Demonstration Notes included.
Concepts: Equilibrium, Le Chatelier’s Principle, endothermic vs. exothermic reactions.
Time Required: 20 minutes
Chemicals Provided: Cobalt chloride solution, hydrochloric acid, silver nitrate solution.
Note: Perform this demonstration in a fume hood or well-ventilated lab.
The Overhead Equilibrium Reaction—
Chemical Demonstration Kit
By: Jim and Julie Ealy, Retired
The Peddie School, Hightstown, NJ
A colorless solution is placed in a Petri dish on an overhead projector. The solution will become dark orange then colorless again by the addi- tion of certain solutions and solids. A dynamic demonstration to illustrate Le Chatelier’s principle of equilibrium. Demonstration Notes included. Concepts: Le Chatelier’s Principle, equilibrium, complex ions.
Time Required: 15 minutes
Chemicals Provided: Potassium thiocyanate solid and solution, iron(III) nitrate solution and sodium phosphate monobasic.
See free video at flinnsci.com.
Pink and Blue—A Colorful Chemical Balancing Act— Chemical Demonstration Kit
AP8471
Catalog No.
Description
Price/Each
AP5938
Hot and Cold Equilibrium—Le Chatelier’s Principle—Chemical Demonstration Kit
$22.00
Catalog No.
Description
Price/Each
AP8471
Pink and Blue—A Colorful Chemical Balancing Act— Chemical Demonstration Kit
$32.35
CHEMICAL EQUILIBRIUM—DEMONSTRATION KITS continued on next page.
The Overhead Equilibrium Reaction—Chemical Demonstration Kit AP8462
Catalog No.
Description
Price/Each
AP8462
The Overhead Equilibrium Reaction— Chemical Demonstration Kit
$28.40