Florida State University
Florida State University: Intermolecular Forces: Changes of State
Discusses the changes of state that can occur for the three different types of matter (solids, liquids, and gases) and different types of heat energy that have been defined by scientists.
Frostburg State University
Frostburg State Chemistry Online: Water Bond Angles & Phase Changes
Describes the bond angle of the water molecule during the transition from liquid to gas state. Also provides several examples and explanations for responses and answers given.
Other
Water on the Web: Studying Heat Budgets of Lakes
Interesting activity that discusses many aspects of the energy in a lake, including the evaporation of the water into gas.
Chem Tutor
Chemtutor: Walking Up the Phase Change Graph
Good exercise graphing a phase change graph from solid to liquid to graph. Includes temperatures and all energy changes for water through this process.