
HEAT PACK REUSABLE
This hand size heat pack contains a supersaturated sodium acetate solution, which at room temperature is in a super cooled liquid state, since it normally freezes well above this at 54°C.
By bending the stainless steel clicker disc, the crystallisation process begins and within a few seconds the entire heat pack has solidified. At the same time heat is released (an exothermic process) because the temperature jumps up to 54°C which is the temperature at which it changes to a solid (freezes). This energy release in the form of heat is because you are forming bonds between atoms to get crystals.
Boiling this reusable heat pack in a pot of hot water until all of the crystals have dissolved, and then leaving it to slowly cool, will allow it to be reused many times.
By bending the stainless steel clicker disc, the crystallisation process begins and within a few seconds the entire heat pack has solidified. At the same time heat is released (an exothermic process) because the temperature jumps up to 54°C which is the temperature at which it changes to a solid (freezes). This energy release in the form of heat is because you are forming bonds between atoms to get crystals.
Boiling this reusable heat pack in a pot of hot water until all of the crystals have dissolved, and then leaving it to slowly cool, will allow it to be reused many times.