Re: molecular weight of dry air

[James Frysinger <frysingerj@COFC.EDU>]

Michael presents a very thorough survey of practices "found in the field" and
the rationales behind them. I have elided most of his posting for brevity
only. (I tend to be long winded and need the space! Grin.)

As one who works with the development of professional standards (national and
international), I find such arguments used frequently by individual authors
or ad hoc committees. While these arguments are valid in that those practices
represent what people often employ, that does not imply that they meet the
requirements of standards other than personal or local conventions --- as I'm
pointing out at the moment to the authors of a proposed draft standard on
transformers for the IEEE that I am reviewing.

There is a natural tendancy for specialized groups to develop their own local
conventions for the sake of brevity. However, that often creates confusion
and arcane writing that is a bane to those who like to read outside their
field. Hence, the movement over the last few centuries towards national and,
later, international consensus standards. Local standards are fine as long as
each document using them states what they are in terms of consensus
standards; unfortunately, this is usually not done. Science (AAAS) recently
published a book review (re: the WMO) that recounts some interesting history
here.

In some cases one can indeed find discrepant consensus standards but we are
moving internationally to harmonization of those in order to remove such
discrepancies. One of the tough battles ahead is harmonization of quantity
names, symbols, and definitions. ISO and IEC are working on this and the U.S.
has a Technical Advisory Group (on which I sit in a very small chair near the
rear) that is a member of the applicable Technical Committee for each of
those organizations.

Jim

On Thursday 13 May 2004 12:54, Edmiston, Mike wrote:
> I use atomic/molecular weight and
> atomic/molecular mass interchangeably.
>
> Is this the "correct" thing to do?
> It depends who you ask.
....
--
James R. Frysinger
Lifetime Certified Advanced Metrication Specialist
Senior Member, IEEE

http://www.cofc.edu/~frysingj
frysingerj@cofc.edu
j.frysinger@ieee.org

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