The first 'reaction' that we tried for our hand warmer involved dissolving potassium carbonate (K 2 CO 3) in water. Potassium carbonate is one of the chemicals left behind in the ashes of burnt wood.

A typical chemical hand warmer contains five ingredients: iron powder, water, salt, charcoal, and vermiculite, a naturally occurring silicate mineral. When exposed to oxygen, the water and salt ...

Disposable hand warmers like HotHands that use chemical ... Plus, its aluminum and ABS construction make it dust, drop, and water-resistant, so you won't need to be afraid to take them with ...

or the best touchscreen gloves, for toasty digits Your standard gel hand warmer has only one setting, and requires you to boil it in water before you can reuse it (you'll find out more in our hand ...