Is a phase change from liquid to gas endothermic or exothermic?
Category:
science
chemistry
Phases and Phase Transitions
Phase Transition | Direction of ΔH |
---|---|
Vaporization (liquid to gas) | ΔH>0; enthalpy increases (endothermic process) |
Sublimation (solid to gas) | ΔH>0; enthalpy increases (endothermic process) |
Freezing (liquid to solid) | ΔH<0; enthalpy decreases (exothermic process) |
Herein, why is solid to liquid endothermic?
This means that as you move from solid to liquid to gas, all accompanying phase changes require the input of heat. Thus, these phase changes are an example of an endothermic reaction. The release of energy is felt as heat as the water vapor goes to water.
Accordingly, which change of phase is endothermic?
Answer and Explanation: Melting, sublimation and boiling are all phase changes which are endothermic.
Thus any transition from a more ordered to a less ordered state (solid to liquid, liquid to gas, or solid to gas) requires an input of energy; it is endothermic. Conversely, any transition from a less ordered to a more ordered state (liquid to solid, gas to liquid, or gas to solid) releases energy; it is exothermic.