current density

The current density $j B$ of a species B in a given point of the solution is obtained by multiplying the flux density of that species at the given point by the Faraday constant $F$ and by the charge number $z B$ of the species:

$j B = z B F N B$

where $j B$ is a vector which indicates the direction in which the charges transported by the species B flow and which gives the number of these charges going through a plane oriented perpendicular to the vector, divided by time and by area, and $N B$ is the flux density of a minor constituent of the solution with respect to a fixed frame of reference.