Answer:
Explanation:
An endothermic reaction is one in which heat is absorbed from the surroundings. The reaction vessel typically feels cold to the touch in the case of an endothermic reaction
An exothermic reaction is one in which heat is released into the surroundings. The reaction vessel typically feels hot in this case.
A cold pack uses the principle of an endothermic reaction. In this case, the cold pack works by cooling the injury through the endothermic reaction mechanism.
A hot pack works the other way round. It releases heat to the injury and makes it heated up through the principle of exothermic reaction
