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Nernst Equation

Skills to develop

Nernst Equation

Electrochemistry deals with cell potential as well as energy of chemical reactions. The energy of a chemical system drives the charges to move, and the driving force give rise to the cell potential of a system called galvanic cell. The energy aspect is also related to the chemical equilibrium. All these relationships are tied together in the concept of Nearnst equation.

Walther H. Nernst (1864-1941) received the Nobel prize in 1920 "in recognition of his work in thermochemistry". His contribution to chemical thermodynamics led to the well known equation correlating chemical energy and the electric potential of a galvanic cell or battery.

Electric Work and Gibb's Free Energy

Energy takes many forms: mechanical work (potential and kinetic energy), heat, radiation (photons), chemical energy, nuclear energy (mass), and electric energy. A summary is given regarding the evaluation of electric energy, as this is related to electrochemistry.

Electric Work

Gibb's Free Energy

The General Nernst Equation

The Nernst Equation at 298 K

Example 1

Example 2

Example 3

Example 4

Confidence Building Questions

Understanding is the key. Take time to understand it, there is no point in rushing.

cchieh@uwaterloo.ca