Why are freezing, condensation and deposition exothermic processes?
1 Answer
Feb 26, 2017
Because all of these slow molecular motion, i.e. require the extraction of heat from the system.
Exothermic by definition means the release of heat from a system. Any process that slows down the particles in the system due to heat flow outwards is therefore exothermic.
- Freezing has particles of a liquid slow down to form a lattice structure and become a solid phase.
- Condensation has particles of a gas slow down to form intermolecular forces and transition into a liquid phase.
- Deposition has particles of a gas slow down to form a lattice structure, becoming a solid and skipping the liquid phase.
Thus, the above three processes are exothermic with respect to the system.