Re: molecular weight of dry air

[Robert Cohen <Robert.Cohen@PO-BOX.ESU.EDU>]

On Thursday, May 13, 2004 12:13 PM, James Frysinger wrote:

> [snip]
> Atomic mass has units of mass. That's where it gets its 
> quantiy name.  It can be stated in kilograms (awkward), 
> yoctograms (1 yg is 10^-24 g), or unified atomic mass 
> units. Thus, it is not dimensionless. Chemists, for reasons 
> known to themselves, may use a casual practice of omitting 
> the "u" symbol and thus making those values appear 
> unitless, though they are not.
> [snip]

I am used to representing the atomic mass in units of
grams/mole (which is equivalent to u/atom), i.e. the atomic
mass of C-12 is 12 g/mole.  Is it improper to refer to that
as atomic mass (since it doesn't have units of mass)?  If
so, what is the proper name?  Molar mass density?

Come to think of it, is there a convention for which symbol one
uses to represent the atomic mass in an equation?  If so, is
the same symbol used for the molar mass density?

Boy, I didn't realize how much I didn't know... 

____________________________________________________
Robert Cohen; 570-422-3428; www.esu.edu/~bbq
East Stroudsburg University; E. Stroudsburg, PA 18301