LAW OF THERMODYNAMIC
To determine the thermodynamics of redox reactions, one must first know the standard reduction potentials.
Here is a list of the Nernst equation terms:
- The standard reduction potential, E0, is measured at 298 K and with all solutions at 1 M.
- However, redox reactions do not maintain this ideal state for very long; as soon as the reaction begins, the concentrations of reactants and products begin to change.
- To cope with this discrepancy, Walther Nernst, a German chemist and physicist, developed an equation in the early 20th century to relate reduction potential, temperature, concentration, and moles of electrons transferred. The Nernst equation, named in his honor, is:
Here is a list of the Nernst equation terms:
- E is the corrected potential for substances in non-standard states
- E0 is the standard potential in volts at 298 K
- R is the gas constant, 8.314510 J/(K×mole)
- F is the Faraday constant, 9.6485309 x 104 Coulombs/mole
- n is the number of electrons transferred
- Q is CcDd/AaBb, where the uppercase letters are concentrations, and the lowercase letters are stoichiometric coefficients for the reaction aA+bB→cC+dD