.split() Qeustion

[wxjmfauth at gmail.com]

Le vendredi 16 août 2013 15:23:37 UTC+2, Roy Smith a écrit :
> In article <2d88bc0f-fdcb-4685-87ed-c17998dd3137 at googlegroups.com>,
> 
>  wxjmfauth at gmail.com wrote:
> 
> 
> 
> > A chemist has to work and is always working in mole; as his
> 
> > balance can only measure a mass, the calculation mole <-> mass
> 
> > is always mandatory.
> 
> 
> 
> That's because chemists are lazy.
> 
> 
> 
> The recipe says, "Add one mole of carbon atoms".  So, does the chemist 
> 
> follow the recipe and count out 6.022 x 10^23 atoms like he's supposed 
> 
> to?  No.  He says, "I don't have time for that.  I'll just weigh out 12 
> 
> grams.  Good enough for government work."  Sheesh.

--------

You don't understand the concept of "mole".

In this formal reaction

Na  + Cl   -->   NaCl

the chemist combines *one mole* of sodium and *one
mole* of chlorine to get *one mole* of sodium chloride
(cooking salt).

It's independent of the number of "particles" in a mole.

It's not a question of laziness, the chemist can only weight
22.98 g of sodium to work with one mole of sodium, because the
nature is like this.


The work with relative quantities has a name: stoichiometry.


jmf