> Matthew Zotter wrote:
>
> 2002 NOV 24 SUN
>
> What society defined standard atmospheric pressure to be 101.325 kPa
> (I know the value came from 760 torr) and standard gravity to be
> 9.80665 m/s^2? Is standard room temperature 293.15K or 298.15 K or
> both? Do any of you know were I could get a thermometer that reads in
> kelvins.
Welcome to the list, Matthew! Folks, Matthew and I have corresponded
before and I encouraged him to join this list. Play nice!
"Standard Temperature and Pressure (STP)" was defined at one time by
the International Union of Pure and Applied Chemistry (IUPAC). Perhaps
they were joined in that by the IUPAP (same thing but for Physics). I
don't know if those are still accepted definitions with that field (or
fields if physics is included), but at least in physics I hardly ever
see that term used. The SI values for those defined parameters are
101.325 kPa and 273.15 K.
The SI brochure does not define STP. However, one sees those the
equivalent value for Standard Pressure in the appendix of the brochure,
specifically on page 123, clause 2.5, the entry for the 10th CGPM
Resolution 4 (1954). This is of course pre-SI, but I see nothing
abrogating it. Let's face it, the SI folks have pretty much gotten away
from defining standard values of anything except those needed to define
units (e.g., the definition of the candela). Matthew, you can download a
free copy of the SI brochure---the defining document!---at the links
provided on
http://www.cofc.edu/~frysingj/SIreferences.htm
Bill Potts's SI Navigator is also an excellent site and the page cited
above has a link to it as well as to NIST, the USMA, and others. Since
you are relatively new to the world of standards, you may wish to read
the material at the bottom of my page, as well.
The value for "standard gravitational acceleration", g_n ("g sub n") is
given today by the ISO in a very expensive standard that is not
available on line. Again, in the appendix of the SI brochure, page 118,
clause 2.2, the entry for the 3rd CGPM (1901), one can see that that
value listed. Again, this predates the SI and so it is not in the main
body of the brochure.
There is no international standard for "room temperature". Some members
of this list have taken outdoor thermometers (the big dial types) and
have made their on Kelvin scales for them.
Again, welcome aboard!
Jim
--
Metric Methods(SM) "Don't be late to metricate!"
James R. Frysinger, LCAMS http://www.metricmethods.com/
10 Captiva Row e-mail: [EMAIL PROTECTED]
Charleston, SC 29407 phone: 843.225.6789
