Page 159 - Demo

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Oxidation and Reduction
157
Oxidation and Reduction—Demonstration Kits,
continued
The Overhead Oscillating Clock—
Chemical Demonstration Kit
By: The Flinn Staff
Oscillating clock reactions are captivating due to their colorful and unpredictable changes. This variation of a classic oscillating reaction is easily performed on an overhead projector. Simply place a Petri dish on the overhead, add three solutions and mix. In a short while blue dots appear on an orange background. The blue dots expand, new dots appear and the dish is filled with concentric blue rings spreading through a sea of orange. The reaction continues for 30 minutes and can be restarted by simply swirling the dish. Demonstration Notes are included.
Concepts: Oscillating reactions, oxidation–reduction, reaction mechanisms.
Time Required: 30 minutes
Chemicals Provided: Acidified sodium bromate solution, malonic acid solution, sodium bromide solution, and ferroin solution.
Vanishing Valentine—
Chemical Demonstration Kit
By: Mike Shaw
West Stokes High School, King, NC
Watch your valentine vanish and then reappear with this favorite holiday demonstration! Simply shake a flask containing a colorless solution to introduce oxygen. The solution will change to a bright pink valentine color. Then allow the solution to sit undisturbed and observe as the solution fades back to colorless. The oxidation– reduction cycle can be repeated many times. Demonstration Notes included.
Concepts: Oxidation–reduction, indicators.
Time Required: 15 minutes
Chemicals Provided: Dextrose solution, sodium hydroxide solution, and resazurin solution.
The Reappearing Pumpkin—
Chemical Demonstration Kit
By: The Flinn Staff
Perform some of your Halloween magic with this fun demonstration. A slight variation of the classic “Blue Bottle Experiment” allows a pump- kin face to disappear and then reappear over and over again. Shake the flask and the pumpkin face disappears as the dark blue color masks the appearance of the pumpkin face. Undisturbed, the pumpkin magically reappears again!
Concepts: Oxidation–reduction.
Time Required: 10–15 minutes
Chemicals Provided: Sodium hydroxide, glucose, yellow food color- ing, and methylene blue.
The Overhead Oscillating Clock— Chemical Demonstration Kit AP2089
Vanishing Valentine— Chemical Demonstration Kit AP5929
Catalog No.
Description
Price/Each
AP2089
The Overhead Oscillating Clock— Chemical Demonstration Kit
$31.25
Catalog No.
Description
Price/Each
AP5929
Vanishing Valentine— Chemical Demonstration Kit
$20.90
Catalog No.
Description
Price/Each
AP6384
The Reappearing Pumpkin— Chemical Demonstration Kit
$24.80
GP3095
Florence Flask, 1000-mL, Flat Bottom
16.70
The Reappearing Pumpkin— Chemical Demonstration Kit AP6384