This number was not counted.
To measure the amount of electrons in this unit are the result of the experiment used by Robert Millikan and the definition of coulomb in the international system of units, this definition is as follows:
A Coulomb (C) is the amount of electric charge passing through the cross section of a driver in a second, when the driver circulates an Amper.
The experiment allowed Millikan find the burden of the electron in units coulomb and therefore is able to estimate the number of electrons in a coulomb.
The issue now moves to the definition of an Amper in SI; this is defined as:
Ampere is the intensity of a steady flow maintained that two drivers in parallel, straight, long endless, circular section despicable and located at a distance of one meter of each other in a vacuum, would produce a force equal to 2 • 10 Λ- 7 newton per metre. Its symbol is A.
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