1. Particles get more kinetic energy and begin rotating around each other. There isn’t enough energy to break the intermolecular attractions, so the particles remain close (liquid). The energy required to melt a solid is called the heat of fusion. Melting - solid to liquid

2. Freezing - liquid to solid Particles lose kinetic energy and slow down. Attractive forces between particles become stronger than the particles’ motion, so the particle sget closer together and begin merely vibrating in place. The amount of heat the particles must lose to turn into a solid is called the heat of fusion.

3. Types: Boiling - rapid; gas bubbles are produced throughout. Evaporation - slow; occurs at the surface. Liquid particles gain enough kinetic energy to overcome forces between the particles and they begin translational motion; this energy is called the heat of vaporization. Vaporization - liquid to gas

4. Evaporation is a cooling process. Particles in a liquid gain kinetic energy. They leave as gas particles (taking the energy away with them). This leaves less energy in the liquid, therefore cooling down what is left.

5. Condensation - gas to liquid Particles lose kinetic energy, slow down, and come closer together. Intermolecular forces become strong enough to make particles merely rotate around each other. The energy they lose to turn into a liquid is the heat of vaporization.

6. Sublimation - solid to gas A solid changes directly to a gas without going through the liquid phase. o Dry ice - carbon dioxide o Iodine o Frost