On Sat, Nov 19, 2011 at 5:05 PM, Peter Heckert <peter.heck...@arcor.de> wrote: > Am 19.11.2011 22:56, schrieb Harry Veeder: >> >> If the same water is _theoretically_ supposed to boil at the same >> precise temperature at a given pressure, I just don't understand how >> water can _theoreticallly_ survive as a liquid drop while surrounded >> by steam which is above the boiling point. In other words, the theory >> that the same water always boils at the same _precise_ temperature for >> a given pressure is an idealisation and an approximation. > > If a water droplet vaporizes, the local pressure increases and this stops > vaporization. Vaporization at air pressure means an 1700 times increase of > volume.
If that is the real reason, then water in a pot on a stove should never boil at atmospheric pressure because "the local pressure increases and stops the boiling". >> My conclusion is consistent with Prof. Hasok Chang (Cambridge >> university) experimental finding that the same water does not always >> boil at the same precise temperature for a given pressure. In >> particular he has shown the surface characteristics of a boiler can >> lower the boiling point by two or three degrees. He also says such >> anomalous behaviour is well known among people who work with with >> steam but it has been ignored or dismissed by the academy. > > In this case there should be steam at lower temperature than the boiling > point. > If this is possible, then it is an exotic effect, because this is rarely > observe. > Its an interesting claim, but it should be proven by experiment, before it > can been considered true. > > Peter Prof Chang has observed it and he says it is routinely observed but it is just ignored because it doesn't fit theory. Harry
