Cold packs are designed to become very cold when activated. When the pack is activated, a chemical reaction occurs to make the temperature of the cold pack decrease. What must be true of this chemical reaction? The reaction releases energy to its surroundings. The products and reactants have the same amount of energy. The products have less energy than the reactants. The reaction absorbs energy from its surroundings.

Question

Cold packs are designed to become very cold when activated. When the pack is activated, a chemical reaction occurs to make the temperature of the cold pack decrease. What must be true of this chemical reaction?   The reaction releases energy to its surroundings.   The products and reactants have the same amount of energy.   The products have less energy than the reactants.   The reaction absorbs energy from its surroundings.

australopithecus · Answer

The reaction that occurs when you break ice packs is endothermic, it absorbs heat. 

Endothermic reactions are unfavorable in terms of enthalpy, but they can occur if the resulting reaction results in an increase of entropy significant enough to overcome the unfavorable change in enthalpy.

Btw, I recommend looking up and memorizing the definitions of entropy, and enthalpy. They are very important concepts in chemistry.