Final answer:
The statement is false because not all processes on a heating curve are endothermic. The total energy remains constant as per the conservation of energy, and the heating curve may represent both endothermic (absorbing energy) and exothermic (releasing energy) processes.
Step-by-step explanation:
The statement is False. On a heating curve, while energy is indeed added to a system, not all processes depicted on a heating curve are endothermic. During phase changes where a substance melts or vaporizes, the added energy is used to break intermolecular bonds, which is an endothermic process. However, once a phase change is complete and temperature begins to rise, the heat energy is contributing to an increase in the kinetic energy of the molecules, not to a phase change. While changes of state in the heating curve do indicate an endothermic process, temperature increases in a single phase are not necessarily endothermic.
According to the law of conservation of energy, the total energy in an isolated system remains constant. During an endothermic process, heat is absorbed from the surroundings, resulting in a temperature decrease in the surroundings. However, the energy of the system plus surroundings remains constant overall.
Moreover, the second law of thermodynamics implies that in any cyclical process, some energy is rendered unavailable for work due to inefficiencies such as heat loss to the environment. Heat transfer of energy can be either positive (endothermic) or negative (exothermic), depending on whether the system absorbs or releases heat.