JCE Software Chemistry Comes Alive!
Briggs-Rauscher Monitored with Electrodes

Changes in electrochemical potential are demonstrated.

View slide thumbnails.
View Slide Thumbnails
  Next movie.
View Next Movie
 

3.5 MB, 46 seconds

File: MOVIES/OSCRXBR/BR3.MOV

Voiceover
A solution of malonic acid, starch indicator, and manganese(II) catalyst is added to a solution of hydrogen peroxide, iodate, and sulfuric acid. The electrical potential of the solution is monitored with a platinum electrode attached to a strip chart recorder. Each color change is accompanied by a change in voltage. As the reaction proceeds, the time between color and voltage changes increases. Eventually the color oscillations will no longer be observed, and the voltage oscillations will become very small. The generation of iodine, however, will continue until one of the reactants is used up.


Designer and Demonstrator:  
  Frederick Mattes Hastings College, Hastings, NE 68902
Video:  
  Jerrold J. Jacobsen University of Wisconsin - Madison, Madison, WI 53706
Voice:  
  G. Earl Peace Jr. University of Wisconsin - Madison, Madison, WI 53706
Text:  
  Frederick Mattes Hastings College, Hastings, NE 68902
  Kelly Houston Jetzer University of Wisconsin - Madison, Madison, WI 53706
  David Phillips Wabash College, Crawfordsville, IN 47933