Electrochemical techniques

Abstract

The electrical properties of a solid metal conductor, such as copper, can be defined in a simple manner by its conductivity, which is a measure of how easily electricity passes through it. The situation becomes more complex when the geometry of the conductor is changed, for example into a coil, and alternating current is used. However, under direct-current conditions the current passing through a conductor is defined by Ohm’s law:

$$ V=RI $$

where V(in volts) is the voltage across the conductor of resistance R (ohms) which results in a current of I (amperes). This simple treatment cannot be extended to the conduction of electricity, even as direct current, through solutions due to the presence of a number of additional effects. First of all, the nature of the solutions themselves, with respect to the presence of suitable conducting ions, and secondly the interaction between the electrodes placed in the solution and the solution components, must be considered.