Clicker #1 Which is lower in potential energy and more stable? unburned match or burned match A) unburned match B) burned match
Exothermic: more energy leaves the system overall Endothermic: more energy goes into the system overall 2H2 + O2 2H2O 2H2O 2H2 + O2
Example #1 Is the freezing of water an endothermic or exothermic process? (The system is underlined.) Exothermic
Clicker #2 Is the boiling of water an endothermic or exothermic process? (The system is underlined.) A) endothermic B) exothermic
Example #2 Is an activated cold pack an endothermic or exothermic process? (The system is underlined.) Endothermic
Clicker #3 Is an activated hot pack an endothermic or exothermic process? (The system is underlined.) A) endothermic B) exothermic
Clicker #4 Is a racquetball frozen by liquid nitrogen an endothermic or exothermic process? (The system is underlined.) A) endothermic B) exothermic
Example #3 Is the thermite reaction (the chemical reaction) an endothermic or exothermic process? (The system is underlined.) Exothermic