Discuss the concept of cell potential and how i... - SS2 Chemistry Electrochemistry Question

Cell potential, also known as electromotive force (EMF), is a measure of the driving force behind a redox reaction in an electrochemical cell. It indicates the voltage or electrical potential difference between the electrodes of the cell. Cell potential is denoted by the symbol Ecell and is measured in volts (V).

The cell potential determines the spontaneity of a redox reaction. If the cell potential is positive (Ecell > 0), the reaction is spontaneous and proceeds in the forward direction. Conversely, if the cell potential is negative (Ecell < 0), the reaction is nonspontaneous, and an external energy source is required for the reaction to proceed.

The cell potential is calculated using the Nernst equation:

Ecell = E°cell - (RT/nF) x ln(Q)

where E°cell is the standard cell potential, R is the gas constant, T is the temperature in Kelvin, n is the number of moles of electrons transferred, F is the Faraday constant, and Q is the reaction quotient.

The standard electrode potential (E°) is the cell potential when all reactants and products are in their standard states (usually at 298 K, 1 atm pressure, and 1 M concentration). It is a measure of the tendency of a half-cell reaction to occur. The standard electrode potentials are tabulated and provide a reference point for comparing different redox reactions.

To calculate the cell potential using the standard electrode potentials, the following equation is used:

E°cell = E°cathode - E°anode

The standard electrode potentials allow for the determination of the cell potential without the need for actual cell measurements. They provide valuable information about the relative strengths of oxidising and reducing agents and allow predictions about the feasibility and direction of redox reactions.