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Chemical Reactions
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Chemical Reactions—Demonstration Kits,
continued
Thionin—The Two-Faced Solution—
Chemical Demonstration Kit
By: The Flinn Staff
“Elegant” best describes this wonderful demonstration. A large beaker containing a purple solution is placed on an overhead projector. Aluminum foil is placed under the beaker so only half the beaker will be exposed to direct light. Switch the overhead lamp on and in a matter of seconds, the side of the beaker exposed to the light turns colorless. The unexposed side remains purple. The intense light causes iron(II) to reduce thionin in an acidic solution. The thionin is photochemically reduced—a visible example of the conversion of light energy to chemi- cal energy. Chemical solution may be used over and over again. Concepts: Light-activated reactions, indicators.
Time Required: 15 minutes
Chemicals Provided: Thionin, sulfuric acid solution, iron(II) sulfate.
Catalog No. Description
AP8845 Thionin—The Two-Faced Solution—
Chemical Demonstration Kit
The Effervescent Oscillator—
Chemical Demonstration Kit
By: Jim and Julie Ealy, Retired
The Peddie School, Hightstown, NJ
Price/Each $26.30
Thionin—The Two-Faced Solution—Chemical Demonstration Kit AP8845
Oscillating reactions typically involve eye-catching color changes but here’s a unique one where the oscillations are between the genera- tion and cessation of gas bubbles. A colorless solution will effervesce intensely and then the bubbling will decrease and then increase again, etc. The oscillations will continue for several minutes. Demonstration Notes included.
Concepts: Oscillating reactions, supersaturation, exothermic reactions. Time Required: 15 minutes
Chemicals Provided: Acidified ammonium sulfate solution and sodium nitrite solution.
Catalog No. Description
AP8658 The Effervescent Oscillator—Chemical Demonstration Kit
Opening Day—Multi-Demonstration Kit
By: The Flinn Staff
Price/Each $26.95
The Effervescent Oscillator—Chemical Demonstration Kit AP8658
Welcome your students to the “wonderful world
of chemistry!” Five colorful and engaging demonstrations have been selected to help students develop observational and critical-thinking skills—and to get them excited about the amazing science that lies ahead.
• “Think Tube” will have students scratching their heads in wonder.
What’s inside the tube?
• Addchunksofdryicetovariouscoloredsolutions,thenwatchasthesolu- tions immediately begin to “boil” and change color. What’s going on here?
• Dip a red sponge into a red solution—the sponge turns blue! Dip the blue sponge into a blue solution and the sponge turns red!
• Passing electric current through a green solution produces gas bubbles at each pencil lead electrode and a rainbow of color changes.
• Fascinating chemical reaction “rotates” back and forth between yellow and blue.
Concepts: Hypothesis, models, pH indicators, acids and bases, electroly- sis, decomposition reactions, oscillating reactions, reaction mechanisms. Time Required: One full class period
Materials Provided: Ammonia solution, hydrochloric acid solution, sodium sulfate, universal indicator solution, bromcresol green indica- tor solution, bromthymol blue indicator solution, hydrogen peroxide solution, methyl red indicator solution, phenol red indicator solution, acidified potassium iodate solution, blue and red food dyes, sodium hydroxide solution, starch–malonic acid–manganese(II) sulfate solu- tion, 9-V battery, battery clip with alligator leads, disposable Petri dish, indicator sponge, pencil leads, Think Tube assembly.
Note: Common laboratory glassware and equipment are required but not provided.
Catalog No. Description Price/Each AP7165 Opening Day—Multi-Demonstration Kit $77.45
Opening Day— Multi-Demonstration Kit AP7165
CHEMICAL REACTIONS—DEMONSTRATION KITS continued on next page.