Larry Brasfield wrote:
"John Fields" wrote in message ...
Since this a technical forum and we _do_ have ground rules, I believe
we generally agree that, unless otherwise specified, standard pressure
is defined as 760 millimeters of mercury and standard temperature is
defined as zero degrees celcius.
I believe that in this forum we assume temperature is a
variable that must be accommodated in design, unless
otherwise stated. I cannot imagine why any unstated
temperature would be assumed to be 0 oC. I suppose
sea-level atmospheric pressure is often assumed, but
where it matters, it should not be assumed at all.
While the boiling point of water is dependent on pressure, the
freezing point, I believe, is not.
You might want to consider the "triple point" of water,
below which pressure "melting point" is meaningless and
the "freezing point" varies considerably with pressure.
At least, not to a great extent. I don't have any data to support
that position, but I'd love to see some, if it's out there.
See: http://www.lsbu.ac.uk/water/phase.html
Using the usual meaning of "freezing" which is the transition from
liquid to solid, that graph shows "freezing" occurring at 273K over a
million to one range in pressure. I would say that the statement "While
the boiling point of water is dependent on pressure, the freezing point,
I believe, is not" is essentially true- to all except a nitwit like you.