What is the difference between endothermic and exothermic processes?

Endothermic and exothermic processes are two fundamental concepts in thermochemistry that describe the flow of heat in chemical reactions and physical changes. The correct answer highlights that endothermic processes absorb heat from their surroundings, leading to a decrease in the temperature of the immediate environment. This absorption of heat is essential for certain reactions to proceed, such as photosynthesis in plants or the melting of ice.

On the other hand, exothermic processes release heat, which can raise the temperature of the surroundings. Common examples include combustion reactions, where a substance reacts with oxygen to produce heat and light, or the formation of water from hydrogen and oxygen.

Understanding these definitions is crucial because they explain the behavior of substances during phase changes and reactions, as well as their energy requirements and products. The other options either inaccurately describe the definitions or mistakenly suggest that there is no distinction between the two processes.