Originally Posted by Ormand
No, you are showing your ignorance, again. It is PHYSICS, not chemistry. There is no chemical reaction involved, merely a change of state. Richard Feynman, genius and PHSICS professor discusses evaporation in the first chapter of his classic book, "Six Easy Pieces". Might get somebody to explain it to you. While they are explaining, they might mention that the other liquids in the coolant evaporate, just like water. Ethylene glycol or propolyne glycol, it doesn't matter. And modern cooling systems are pressurized to 15psi, or higher. The overflow tanks on most cars are plastic- and they are NOT designed to that pressure. At least not in the real world. Oh yeah, look under the hood. Altmas have plastic overflow/expansion tanks.
Chemistry (from Egyptian kēme (chem), meaning "earth") is the science concerned with the composition, structure, and properties of matter, as well as the changes it undergoes during chemical reactions.
Physics is the science studying the concept of matter and its motion, as well as space and time — the science that deals with concepts such as force, energy, mass, and charge.
i'm pretty sure it's chemistry/thermodynamics. just because a physicist wrote it in his book doesn't mean that it's physics. if you are talking about the entire cycle, then it would be thermo (which is derived from physics)
anyways, besides that point. how about getting back on track with the subject