.split() Qeustion

Gregory Ewing greg.ewing at canterbury.ac.nz
Sat Aug 17 19:30:14 EDT 2013


wxjmfauth at gmail.com wrote:
> Na  + Cl   -->   NaCl
> 
> the chemist combines *one mole* of sodium and *one
> mole* of chlorine to get *one mole* of sodium chloride
> 
> It's independent of the number of "particles" in a mole.

The actual number chosen for the unit is arbitrary, but
number of particles is still the central issue. The
important thing is to have the *same* number of particles
of Na and Cl.

Weight only comes into it because it's totally impractical
to count particles. And the particular number 6.02e23 is
chosen because it happens to give a convenient relationship
between number of particles and grams. If chemists had
decided to use ounces instead, the number would be different.

-- 
Greg



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