Energetics

• Exothermic


  Describes a reaction in which energy is transferred to the surroundings.
• Endothermic


  Describes a reaction in which energy is transferred from the surroundings.
• Chemical potential energy


  Energy stored in the chemical bonds between particles.
• Stability and chemical potential energy are interrelated. Lower potential energy leads to greater stability and vice versa.
• As energy is released in an exothermic reaction, the potential energy of the products is lower than the potential energy of the reactants. This leads to a greater stability of the products than reactants due to this lower potential energy.
• Evaporation, sublimation, and melting are endothermic processes because energy is absorbed from surroundings to increase the kinetic energy of particles and overcome intermolecular forces.
• Condensation, deposition, and freezing are exothermic processes because energy is released to surroundings, decreasing the kinetic energy of particles.