----- A mole is an amount of matter measured in [kg] . The Avogadro's number can only be a dimensionless number, [1] . The Avogadro's constant is the Avogadro's number (of "pieces" or "objects") per mol, [1 / mol].
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. Why did I put this "mole" in the post scriptum? Because there is a tendency on this list to be extremely confused and to compare what is not comparable (eg. comparaison of mole and Python large number, number and radian, byte and unicode transformation unit). jmf -- http://mail.python.org/mailman/listinfo/python-list
