compressed gas....and heat transfer... If you were to take a cylinder of air, at room temp, and lets say it is 100ml in volume. If you were to take this cylinder of air, compress its volume to half its size, how much heat would that create (btu's) and if the heat were to dissipate, would the air inside the cylinder then be back at atmospheric pressure? If not back at atmospheric pressure, and (assuming there is still some pressure) the air were then released, would it reabsorb the energy that was dissipated after it was compressed? i.e. would it then cool the surrounding room back to the original temperature? Thanks!