We know that e=1.6×10−19 C, i.e charge on the electron. The total charge required is 1 Coulomb, q = 1C Therefore we also know that q = n × e, (n = number of electrons on the charge) Hence, n=
q
e
....(1) Substituting all the values in the equation (1) n=
1
1.6
×10−19​=625×1016 So, if 1A current flows through the conductor then 625×1016 electrons flow per second across the cross-section of the conductor.