Question: Can You Make a Hand Warmer?

Ever been outside on a winter day and had your hands get cold? Chances are, you have. Most camping and outdoor themed stores sell hand warmers that use a chemical reaction of some sort to produce a low temperature heat that can help warm up your frozen digits. But, wouldn't it be cool if you could make one of these hand warmers yourself? With this experiment you can! We'll show you what materials you will need, as well as how to perform the experiment! 

Materials Needed:

(Any of The Materials Highlighted in Blue are Clickable Links for Purchasing)

Jelly Crystals

Small cups (2)

Iron filings

Calcium chloride

Zipper-lock bag


Project Procedure:

  1. Fill a cup with 9 oz of water.
  2. Add a generous scoop of Jelly Crystals to the water and wait until the crystals are fully grown. You’ll know that the crystals are done growing when there’s no more water in the cup.
  3. Add 4 tablespoons of the full-grown Jelly Crystals to a zipper-lock bag.
  4. Add 1 tablespoon of iron filings to the bag.
  5. Add 1 1/2 tablespoons of calcium chloride.
  6. Carefully mix the contents of the zipper-lock bag by squishing the bag with your fingers. Once the contents are mixed, seal the bag.
  7. Shake and squish the bag to mix the contents even more. Once mixed, feel the heat coming from the bag.
Posted by Isaac Fornari on 22 December, 2015 elementary, middle school |
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