I understand how a mole works, however, I have no clue how Avogadro got the specific number of 6.02×10^23.
In: 68
Avogadro did not get the number. The constant has his name because he was the first to suggest that it should be constant, or, more precisely, that the volume of gas at given temperature and pressure is proportional to the number of individual particles in that volume. The actual value was derived from some rather advanced thermodynamic and electrodynamic calculations and measurements
about a hundred years after Avogadro’s time.
Specifically, one way was to first determine the charge of a single electron. By observing the motion of tiny charged droplets in an electric field the electric charge of each droplet can be calculated. Since the droplets are tiny, each only has a few extra electrons on it. So the charges of all droplets are going to be integer multiples of some minimum value – the charge of one electron. After getting that, obtaining the Avogadro’s number is as simple as measuring the charge of one mole of electrons and dividing it by the charge of one electron. The charge of one mole of electrons was determined from observing electrochemical reactions (electrolysis) and comparing the amount of charge discharged and the amount (moles) of substance electrolyzed.
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