|
|
| Home > JCE Print > Journal of Chemical Education > Issues >
1998
>
November
> |
|
In the Classroom
|
|
Tested Demonstrations
|
|
The Alginate Demonstration: Polymers, Food Science, and Ion Exchange
|
submitted by: Amy Sue Waldman, Linda Schechinger, Geeta Govindarajoo, and James S. Nowick
Department of Chemistry, University of California at Irvine, Irvine, CA 92697-2025
submitted by: Louis H. Pignolet
Department of Chemistry, University of Minnesota, Minneapolis, MN 55455-0431
Checked by: Ted Labuza
Department of Food Science and Nutrition, 136 ABLMS University of Minnesota, St. Paul, MN 55108
|
|
November 1998
Vol. 75 No. 11
p. 1430
|
|
|
|
| Abstract |
|
We have recently devised a polymer demonstration involving the crosslinking and decrosslinking of alginate, a polysaccharide isolated from seaweed. The polymer is composed of D-mannuronic acid and L-guluronic acid subunits and is a component of cell walls. It is commonly used as a thickener in foods such as ice cream and fruit-filled snacks. For the demonstration, a 2% solution of sodium alginate is poured into a 1% solution of calcium chloride. Nontoxic calcium alginate "worms" form due to crosslinking of the polymer. Alternatively, the commercially available antacid Gaviscon can be used as a source of sodium alginate. The crosslinks can then be broken by shaking the worms in brine. The demonstration is a fine addition to any chemical educator's repertoire of polymer experiments.
|
|
| More Information |
 Citation |
Waldman, Amy Sue; Schechinger, Linda; Govindarajoo, Geeta; Nowick, James S.; Pignolet, Louis H. J. Chem. Educ. 1998 75 1430.
|
Keywords |
demonstrations, polymer chem, food science, ion exchange, outreach, aqueous solution chem
|
History |
Created:
Last Updated: |
June 18, 1999
June 24, 2005
|
|
|
|
|
|
| Home > JCE Print > Journal of Chemical Education > Issues >
1998
>
November
> Page
1430
|
|
|
| JCE HS CLIC |
|
Our Secondary School editors work hard to distill all the JCE materials to produce a fraction of particular interest to high school teachers. We call it CLIC.
|
| Contributions Welcome |
| JCE welcomes your submission |
| Advertisers |
| In recent years we have worked hard to better match our advertisers with our readers. When shopping for chemistry education materials, visit our advertisers' WWW sites first. |
| Be An Ambassador |
| Take JCE along on your outreach missions. Copies of the Journal, guest access to JCE Online, our publications catalog, and more are available for your participants. |
|
