Phase Changes

[itzeelpadillaDis1A]

What are the exothermic phase changes?

[Sue Xu 2K]

Condensation, solidification and deposition are all exothermic phase change that release heat during the process.

[Dylan Mai 1D]

Are we supposed to know the specific terms for those phase changes listed above? Like fusion for example

[Arjun Sharma 1D]

It would probably be a good idea to know the names of the different phase changes in case they just use the specific name w/o description in a problem @Dylan Mai 1D

[Shanmitha Arun 1L]

It would be best to know the enthalpy of fusion and the enthalpy of vaporization as it is used in calculations.

[Christina Bedrosian 1B]

An easy way to think about this is that exothermic releases heat, meaning usually involving cooling, so the phase changes being exothermic would be from gas to liquid (condensation), liquid to solid (freezing), or gas to solid.

[Ishita Monga 1B]

Condensation, solidification and deposition are all exothermic phase change that release heat during the process.

follow up- what is deposition?

[Chem_Mod]

An exothermic reaction is a process by which energy is outputted from the system leaving the products with less overall energy than the reactants. This includes certain phase changes (like melting and condensation) for physical changes of substances, but may also include a reaction with a negative enthalpy of reaction.

[Naomi Jennings 2H]

Condensation, solidification and deposition are all exothermic phase change that release heat during the process.

follow up- what is deposition?

Deposition is the process of a vapor going straight from vapor to solid. It's the reverse of sublimation.

[RohanGupta1G]

Exothermic phase changes are ones that release heat such as a gas turning into a liquid or solid, or a liquid turning into a solid. As the temperature lowers, energy is released and the phase changes.

[Michelle Lee 2E]

Think of exothermic as something that is cooler as a result of a reaction so gas to liquid (condensation: an example is water droplets on a window from fog) and liquid to solid (freezing: ice).
Endothermic, then, would be something retaining heat like ice retaining heat and melting.

[Natalie LeRaybaud 1G]

The exothermic phase changes are the ones that occur going down a heat curve. This is because they are releasing energy during the reaction and therefore have energy as a product and have a negative delta H (enthalpy). This includes freezing, condensation, and deposition as stated above.

[Gwen Peng 1L]

Fusion, vaporization, and sublimation are endothermic processes, whereas freezing, condensation, and deposition are exothermic processes.

[Michelle Lu 1F]

Exothermic reactions release heat, and therefore the product will be colder. This means that the exothermic phase changes are going down the heat curve, including freezing, condensation, and deposition.