A Fun Real-Life Application for Cross-linking and Polymer Chemistry
- Two kit options available: teacher demonstration or student activity
- Required basic labware that you provide.
This activity demonstrates how a simple material extracted from seaweed is used as a common thickening agent for popular candies. Sodium alginate is a long-chain, natural polysaccharide polymer that contains sodium ions. When placed in a solution of calcium chloride, the divalent calcium ions displace the sodium ions and the polymers are quickly cross-linked to form a worm-shaped gel. These gelatinous worms can be safely examined since the polymer is a nontoxic food additive. The demonstration includes enough materials to for 10 repetitions. The activity contains enough materials for 12 student groups to prepare several worms.
Ordering information: Includes Sodium Alginate, Calcium Chloride, Food Coloring, and Syringe. General Glassware/Labware are required but not included.