Materials List: To Infinity and Beyond:
The Amazing Hydrogels

For the entire class to share

  • 12 g calcium chloride (CaCl2) Note: Alternatively, the teacher can use an already prepared solution (0.1M) and dilute as explained in the procedure section.
  • 2 L distilled water (tap water can also be used)
  • 10 g sodium alginate powder (food grade)
  • 110 grams (4 oz) cost around $10; can order through Amazon or other suppliers.
  • 3 different colors of food coloring/dyes (The bottles of food coloring can be shared among all the groups if needed)
  • 1 L beaker to prepare the sodium alginate solution.
  • 1 L beaker to prepare the 0.1M calcium chloride solution (stock solution)
  • 2 250 mL beakers to dilute the stock solution and to prepare 0.05M and 0.02M calcium chloride solutions.

Each group needs

  • 100 mL graduated cylinder (The teacher may choose a pipette or a syringe instead to add calcium chloride in several applications. The amount is specified in the procedure section.)
  • 4 Styrofoam cups or 4 beakers (100 mL)
  • 3 petri dishes (or 3 Styrofoam cups) for gelling