[time-nuts] temperature sensor

[Chuck Harris]

Absolutely nothing limits the temperature of  steam in
air.  It can easily be superheated to thousands of degrees F.

However, at the water/steam interface, the steam will be
exactly 100C at standard pressure as it vaporizes.  Even if the
water is full of dissolved matter, and has a slightly higher
boiling point.

When I calibrate thermometers, I always use well stirred ice
water, and well stirred boiling water.  I can't see getting
enough dissolved matter in distilled water to make enough of
a difference in the boiling point to matter to me.

-Chuck Harris

Attila Kinali wrote:
> On Mon, 21 Jul 2014 18:00:59 -0400
> Chuck Harris <cfharris at erols.com> wrote:
>
>> Steam superheats only if the pressure is raised above standard pressure,
>> otherwise, steam at standard pressure will be exactly 212F, or 100C.
>
> Uhm.. you are the second one claiming this. Could you please explain
> what physics limits the temperature of vapor?
>
> The ideal gas equation says that p*V/T = const, ie that the temperature
> can rise at a constant pressure, as long as the gas is allowed to expand.
>
> 				Attila Kinali
>