Discussion

We found that calcium chloride was the most effective and cost-efficient ionic solid to use in a hand warmer. After performing a calorimetry experiment with five other ionic solids, calcium chloride let to the second highest increase in temperature and was the third cheapest option. It also is low in toxicity and can be safely disposed.

On the other hand, the other ionic solids were either not as exothermic, too expensive, or unsafe. Calcium chloride was a balanced alternative and at the right price, could be a sellout.