Can science really warm your hands
Science will never let your hands freeze!
Warning! Only under adult supervision.
- calcium chloride;
- thermochromic sticker;
- mittens or gloves;
- two resealable plastic bags.
Pour some water into a resealable plastic bag and seal it, then pour some calcium chloride into another. Put the bag with water into the second bag and seal it, then apply a thermochromic sticker. Put on some mittens or gloves and squeeze the bag of water until it opens, allowing the water to leak out and mix with the calcium chloride. The thermochromic sticker changes colors!
When dissolved in water, calcium chloride breaks down into calcium and chlorine ions, which are immediately surrounded by water molecules. They bond especially strongly to calcium ions. This process releases a lot of heat and the thermochromic sticker changes colors! It’s quite comfortable to do this trick in mittens or gloves – it will quickly warm your frozen hands!
A similar experiment is included in the “Thermal effects” set from the MEL Science subscription.