Gross your kids out by drizzling colored alginate (liquefied brown seaweed) into a solution of calcium chloride. When the alginate hits the solution, it instantly polymerizes a skin that surrounds the liquid, forming what appears to be small boogers and eggs. Wonderful polymer reaction and a great example of a chemical change.
This is the same lab as Seaweed Caviar and Instant Worms. We just made a few adjustments so you can use it for Halloween!
Demo Pack includes 7/8 oz. Vial Calcium Chloride powder, 1 oz. Alginate, 1 oz. Food Color, 10 oz. Cup, 1 Pipette $7.95
Study Group Pack includes 4 7/8-oz. Vial Calcium Chloride powder, 4 1-oz. Alginate, 4 1-oz. Food Color, 4 10-oz. Cups, 4 Pipettes $24.95
Classroom Pack includes 12 7/8-oz. Vial Calcium Chloride powder, 12 1-oz. Alginate, 12 1-oz. Food Color, 12 10-oz. Cups, 12 Pipettes $31.95
School Pack includes 4 oz. Calcium Chloride powder, 1 gallon Alginate, 16 oz. Food Color, 120 10-oz Cups, 120 Pipettes $49.95