Page 120 - Demo

118
Flinn Lab Activities and Demonstrations
1-800-452-1261
flinnsci.com
Solutions and Solubility—Laboratory Kits,
continued
Crystal Ornaments—
A Holiday Student Laboratory Kit
By: The Flinn Staff
Add some sparkle to your next holiday celebration by making crystal ornaments. Students make a saturated solution of sodium borate, bend a chenille wire into the desired shape and suspend the wire in the solu- tion. The next day students remove a beautiful crystal-covered ornament from the solution! Art and science combine as students learn about solu- tions and solubility and examine their ornaments under magnification to determine the crystal shape. Suitable for any holiday or seasonal event, this fun activity easily fits into the curriculum whenever these concepts are presented. Includes valuable Notes, detailed background informa- tion, a reproducible student worksheet, and all necessary materials.
Complete for 30 students working individually. Additional chenille wires and sodium borate are available separately.
Solutions and Solubility—Demonstration Kits
Audio Conductivity Tester—
Multi-Demonstration Kit
By: Bob Becker
Kirkwood High , Kirkwood, MO
Students reading a “Caution: Keep away from water!” notice on an electrical appliance may assume all water conducts electricity. Clear up their misconception with this easy-to-assemble conductivity tester that uses a piezoelectric buzzer and emits an audible sound when a circuit is complete. Use the first demonstration to engage students in a lively discussion about why three colorless liquids produce varying sounds— or no sound at all! In the second demonstration, students see and hear the effect concentration has on the conductivity of an electrolyte. The buzzer is sensitive enough to track the diffusion of ions as a few crys- tals dissolve in solution and form a complete circuit. The conductivity of acids and bases is explored in the third demonstration. Listen to the surprising results when an acid and base are combined! Enough chemi- cals are provided to perform each demonstration seven times with one reusable conductivity tester.
Concepts: Electrical conductivity, electrolytes vs. nonelectrolytes, ions. Time Required: 20 minutes
Materials Provided: Ammonia, copper wire, copper(II) sulfate, sodium chloride, vinegar, battery clip with wire leads, Fahnestock clips, Petri dishes, piezo buzzer.
Note: A 9 V battery is required and available separately. See free video at flinnsci.com.
Colorful Salting Out—
Chemical Demonstration Kit
Two colored liquids are layered on top of each other,
one blue and the other yellow. Shake the bottle and the liquid within turns green. Upon standing, the two original colored layers reestablish themselves. This attention-grabbing demonstration is a perfect introduc- tion to concepts like chromatography, intermolecular forces, density and solutions.
Concepts: Chromatography, solutions, non-polar vs. polar, immiscibility. Time Required: 15 minutes
Materials Provided: Isopropyl alcohol, sodium chloride, marker, plastic soda bottle.
SOLUTIONS AND SOLUBILITY—DEMONSTRATION KITS continued on next page.
Crystal Ornaments—A Holiday Student Laboratory Kit AP7413
Catalog No.
Description
Price/Each
AP7413
Crystal Ornaments—A Holiday Student Laboratory Kit
$31.15
Catalog No.
Description
Price/Each
AP7279
Audio Conductivity Tester—Multi-Demonstration Kit
$30.90
AP1430
Transistor Battery (Alkaline), 9-volt
5.65
Audio Conductivity Tester–Multi-Demonstration Kit AP7279
Colorful Salting Out— Chemical Demonstration Kit AP9831
Catalog No.
Description
Price/Each
AP9831
Colorful Salting Out—Chemical Demonstration Kit
$22.15