🚀 go-pugleaf

jml12@cunixa.cc.columbia.edu (Jonathan M Lennox) writes:

>In article <wf_Eage00WB79IkpAh@andrew.cmu.edu> gb29+@andrew.cmu.edu (Guntur N Balaji) writes:
>>Just wondering how Avogadro got to his number.  6.023E23 atoms....
>>Looks like the mysterious Eddington number.  Can someone give a
>>plausible explanation and substantiate Avogadro's number.  Looks like
>>the explanation must be simple, as I can't think of somebody suggesting
>>such a number without knowing quantum theory and etc...:-)

>  I believe that for a significant length of time, the value of
>Avogadro's number was not in fact known, so chemists just used the
>number of moles they had without worrying about how many particles
>this represented (as there was no way of finding this out.)

OK, that all makes sense, but when/who/how (particularly how) did grace
us with 6.02e23?  How do you go about counting the number of carbon atoms
in 12 grams?  Light scattering?  Osmotic theory?  Those all seem too 
insensitive for the number of decimal points I've seen quoted.

A chemist who should bloody well know this,
j godden