Final answer:
The statement is generally true since a cooling curve often signifies an exothermic process where energy is released as the system cools. However, it is important to note that some cooling occurs during endothermic phase changes, such as melting or vaporization, where energy is absorbed.
Step-by-step explanation:
True or False: On any cooling curve, energy is released and therefore it is always exothermic.
This statement is largely true. A cooling curve represents the change in temperature of a system as it cools down and usually transitions from a higher state of energy to a lower state. As the system cools, it releases energy to the surroundings in an exothermic process, often resulting in the formation of bonds, which also releases energy.
According to the second law of thermodynamics, heat transfers from a hotter to a cooler object. This law also implies that during an exothermic reaction, which is represented by a negative enthalpy change (ΔH), the system loses energy, making the products have less energy than the reactants.
However, it's important to understand that not all cooling processes are exothermic. For instance, during an endothermic process, heat is absorbed from the surroundings, causing the temperature of the system to decrease as it undergoes a phase change, such as melting or vaporization.