[R-390] The mole

[Roy Morgan]

At 02:11 AM 11/8/2007, Kenneth G. Gordon wrote:
> > --- Tony Casorso <canthony15 at msn.com> wrote:
> >  > 15 moles, that would be about 3 feet right?...
>Amount of something...usually in Chemistry. Kinda like a
>dozen of something...in this case 6.022 X 10^23 of that
>something. Even if it were inches, it would be a LONG way.

Folks,
At:
http://physics.nist.gov/cuu/Units/mole.html
we find:

"... the International Organization for Standardization (ISO), the CIPM 
gave in 1967, and confirmed in 1969, a definition of the mole, eventually 
adopted by the 14th CGPM (1971):
1. The mole is the amount of substance of a system which contains as many 
elementary entities as there are atoms in 0.012 kilogram of carbon 12; its 
symbol is "mol."

2. When the mole is used, the elementary entities must be specified and may 
be atoms, molecules, ions, electrons, other particles, or specified groups 
of such particles.
        At its 1980 meeting, the CIPM approved the 1980 proposal by the 
Consultive Committee on Units of the CIPM specifying that in this 
definition, it is understood that unbound atoms of carbon 12, at rest and 
in their ground state, are referred to. "

and at:
http://physics.nist.gov/cgi-bin/cuu/Value?kgu
we find:

"kilogram-atomic mass unit relationship
  Value  6.022 141 79 x 1026 u
  Standard uncertainty  0.000 000 30 x 1026 u
   Relative standard uncertainty   5.0 x 10-8
  Concise form  6.022 141 79(30) x 1026 u    "

So there you have it to eight decimal places.

Roy



- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing
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