Page 162 - Demo

Flinn Lab Activities and Demonstrations
Electrochemistry—Laboratory Kits, continued
Build a Solar Cell—Student Activity Kit
160
Integrated
STEM
1-800-452-1261
flinnsci.com
By: The Flinn Staff
STEM Integrated
The energy crisis is real! Update your curriculum
today, and bring hte latest technological develoments
in solar energy research into your classroom. Dye-sensitized solar cells (DSCs) mimic the process that occurs in photosynthesis to harvest sunlight and convert it to electricity. Use this kit to build a DSC and learn about the principles behind its operation. The solar cell consists
STEM
the anode and graphite at the cathode. The titanium oxide iIsntceogratted with
of conductive glass plates coated with nanocrystalline titanium oxide at
a natural dye that absorbs visible light. Light striking the dye surface promotes an electron to a photoexcited state, which transfers an electron into the conduction band of titanium oxide. Electrons migrate through the titanium oxide film and travel through the external circuit to the cathode. The result—electricity from light!
The cells may be prepared in assembly-line fashion—plan for about two hours to complete the setup and demonstration. There are two good stopping points if the entire procedure cannot be completed at one time. Includes conductive glass plates, nanocrystalline titanium oxide, dried hibiscus petals, iodine/potassium iodide electrolyte solution, tealight candle, lens paper, ethyl alcohol, dilute nitric acid, and binder clips for the cells.
Complete with enough materials to make four solar cells. A multimeter can be used to measure the voltage of the solar cell and is available sepa- rately. Includes Flinn Exclusive STEM Integration Guide.
Electrochemistry—Demonstration Kits
Colorful Electrolysis—
Chemical Demonstration Kit
By: Mike Shaw
West Stokes High School, King, NC
Demonstrate simple electrolysis in a very colorful and dramatic way on your overhead projector. A 9V battery supplies the power and universal indicator provides the color show. As electrolysis occurs in the Petri dish, the pH changes at the anode and cathode are different. The solution around the cathode immediately turns purple as hydrogen gas bubbles are formed. At the anode, oxygen is produced and the solu- tion turns orange/red in color. The entire spectrum of universal color changes occurs, reflecting the pH continuum created in the Petri dish. Demonstration Notes are included.
Concepts: Electrolysis, pH.
Time Required: 15 minutes
Materials Provided: 9V battery, battery clips, pencil leads, Petri dishes, sodium sulfate solution, and universal indicator solution.
See free video at flinnsci.com.
Build a Solar Cell—Student Activity Kit AP6916
Catalog No.
Description
Price/Each
AP6916
Build a Solar Cell—Student Activity Kit
$66.15
AP9000
Multimeter
68.20
Catalog No.
Description
Price/Each
AP6467
Colorful Electrolysis— Chemical Demonstration Kit
$26.25
ELECTROCHEMISTRY—DEMONSTRATION KITS continued on next page.
Colorful Electrolysis—Chemical Demonstration Kit AP6467