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Electrochemistry
161
Electrochemistry—Demonstration Kits, continued
Reversible Tin Man—
Chemical Demonstration Kit
By: The Flinn Staff
Grow a beautiful “tin-man” crystal tree using this electrifying demonstration! This quick and simple demonstration will teach oxida- tion–reduction principles and show students the components of a simple electrolytic cell. Students will enjoy watching tin crystals grow before their very eyes across a Petri dish and then quickly “reverse” as the cathode and anode are switched. A true crowd-pleaser! Demonstration Notes and reproducible student worksheets are included.
Concepts: Electrolysis, oxidation–reduction, anode, cathode.
Time Required: 15 minutes
Materials Provided: Tin(II) chloride solution, 9V battery, battery cap with alligator clip leads, Petri dish.
See free video at flinnsci.com.
Writing with Electricity—
Chemical Demonstration Kit
By: Paul Price
Trinity Valley School, Fort Worth, Texas
Get a charge out of writing with electricity! Demonstrate the key concepts of electrochemistry, including anodic and cathodic reactions, by using a copper “pen” to follow the flow of electrons in the electroly- sis of aqueous potassium iodide. Students will observe secret messages that appear in filter paper containing starch and phenolphthalein indica- tors. The blue-black starch iodine complex is visible when the copper pen is negative, and the red color of phenolphthalein in base appears when the pen is positive. Identify the reactions responsible for each color change—and watch the electrons and concepts flow!
Concepts: Electrochemistry, acid–base indicators.
Time Required: 15 minutes
Materials Provided: Potassium iodide, starch, phenolphthalein indi- cator solution, aluminum pan, filter paper, 9V battery, battery clips, copper wire, and disposable pipets.
The Electrochemical Clock Kit—
Irwin Talesnick’s Orange Juice Clock
By: Irwin Talesnick, Chemistry Dept., Retired Queens University, Kingston, Ontario, Canada
Arouse student curiosity. Irwin Talesnick’s famous orange juice clock is guaranteed to get your students thinking! How does the clock work? How long will the clock run on orange juice? Can you use something other than orange juice? Hundreds of questions can be asked and investigated. Allow students to design and do their own experiments. Instructions and teaching tips are provided.
Concepts: Electrolysis, oxidation–reduction, anode, cathode.
Time Required: 15 minutes
Materials Provided: A 3-color, 24-hour clock face (Atomic number 1, H, Hydrogen, through to Atomic number 24, Cr, chromium), complete clock assembly, hook-up wires, electrodes, orange juice. All you need to provide is a stiff piece of cardboard or wood on which to hang the clock.
See free video at flinnsci.com.
Reversible Tin Man— Chemical Demonstration Kit AP6867
Catalog No.
Description
Price/Each
AP6867
Reversible Tin Man— Chemical Demonstration Kit
$34.05
Writing with Electricity—Chemical Demonstration Kit AP7312
Catalog No.
Description
Price/Each
AP7312
Writing with Electricity— Chemical Demonstration Kit
$39.60
Catalog No.
Description
Price/Each
AP8718
The Electrochemical Clock Kit— Irwin Talesnick’s Orange Juice Clock
$55.25
The Electrochemical Clock Kit AP8718