Nernst Equation Calculator

Nernst Equation Calculator:

Enter the values of standard electrode potential, E_0(V), ideal gas constant, R_(J/mol.K), temperature, T_(K),   number of electrons, Z, Faraday constant, F_(C/mol) and reaction quotient, Q to determine the value of Electrode Potential, E_(V).

Enter Standard Electrode Potential:		V
Enter Ideal Gas Constant:		J/mol.K
Enter Temperature:		K
Enter Number of Electrons:
Enter Faraday Constant:		C/mol
Enter Reaction Constant:
Result – Electrode Potential:		V

Nernst Equation Formula:

The Nernst equation is a fundamental equation in electrochemistry that allows the calculation of the electrochemical potential (or cell potential) under non-standard conditions. It is based on the principle that the electrical potential of an electrochemical cell is dependent on the concentrations of the reacting species and the temperature of the system. The equation applies to redox reactions and is derived from the Gibbs free energy equation.

The Nernst equation accounts for the effect of concentration gradients on the potential difference between two electrodes in an electrochemical cell. It is particularly useful for determining the equilibrium potential of ions across a membrane, such as in biological systems or batteries. The equation incorporates the ideal gas constant (R), temperature (T), the number of electrons transferred in the reaction (Z), and the Faraday constant (F), all of which influence the resulting potential.

At standard conditions, the Nernst equation simplifies to the standard electrode potential, but it becomes more complex when concentrations differ from standard values. The equation is essential for understanding how the cell potential changes with varying conditions and can be used to predict the direction of a redox reaction based on the concentration of ions.

Electrode Potential, E_(V) in volts of an electrochemical cell is equal to the standard electrode potential, E_0(V) in volts minus the product of the ideal gas constant, R_(J/mol.K) in Joules per mole Kelvin and the temperature, T_(K) in Kelvin, divided by the product of the number of electrons, Z involved in the redox reaction and the Faraday constant, F_(C/mol) in Coulombs per mole, multiplied by the natural logarithm (ln) of the reaction quotient, Q.

Electrode Potential, E_(V) = E_0(V) – (R_(J/mol.K) * T_(K) / Z * F_(C/mol)) * ln(Q)

E_(V) = electrode potential in volts, V.

E_0(V) = standard electrode potential in volts, V.

R_(J/mol.K) = ideal gas constant in Joules per mole Kelvin, J/mol.K.

T_(K) = temperature in Kelvin, K.

Z = number of electrons.

F_(C/mol) = Faraday constant in Coulombs per mole, C/mol.

Q = reaction constant.

Nernst Equation Calculation:

1. Given: E_0(V) = 0.34V, R_(J/mol.K) = 8.314 J/mol.K, T_(K) = 298K, Z = 2, F_(C/mol) = 96,485 C/mol, Q = 0.01.

Electrode Potential, E_(V) = E_0(V) – (R_(J/mol.K) * T_(K) / Z * F_(C/mol)) * ln(Q)

E_(V) = 0.34 – (8.314 * 298 / 2 * 96485) * ln(0.01)

E_(V) = 0.34 – (2477.372 / 192970) * (-4.605)

E_(V) = 0.34 + 0.061

E_(V) = 0.401 V.

2. Given: E_(V) = 0.25V, R_(J/mol.K) = 8.314 J/mol.K, T_(K) = 298K, Z = 2, F_(C/mol) = 96,485 C/mol, Q = 0.01.

Electrode Potential, E_(V) = E_0(V) – (R_(J/mol.K) * T_(K) / Z * F_(C/mol)) * ln(Q)

E_0(V) = E_(V) + (R_(J/mol.K) * T_(K) / Z * F_(C/mol)) * ln(Q)

E_0(V) = 0.25 + (8.314 * 298 / 2 * 96485) * ln(0.01)

E_0(V) = 0.25 – (2477.372 / 192970) * (-4.605)

E_0(V) = 0.25 – 0.059

E_0(V) = 0.309V.