Equação de Nernst
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- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
Nernst
About this calculator
The Nernst equation is a fundamental tool in electrochemistry for calculating the voltage of an electrochemical system. It allows determining the voltage of a potential equilibrium in function of the concentration of ions and the temperature.
The Nernst equation formula is E = E° − (RT/nF)·lnQ, where E° is the equilibrium potential, R is the gas constant, T is the temperature in Kelvin, n is the number of electrons transferred, F is the Faraday constant, and Q is the ratio between the concentrations of ions.
The Nernst equation is particularly useful in electrochemical processes, such as electrolysis and electropolishing, where the voltage of an electrochemical system is critical for controlling chemical reactions.
It is worth noting that the Nernst equation is a simplified approximation and does not take into account factors such as electrolytic resistance and tension distribution in the system.
Frequently asked questions
What is the Nernst equation?
The Nernst equation is a mathematical formula for calculating the voltage of an electrochemical system in function of the concentration of ions and the temperature.
When to use the Nernst equation?
The Nernst equation is useful in electrochemical processes, such as electrolysis and electropolishing, where the voltage of an electrochemical system is critical for controlling chemical reactions.
Cautions when using the Nernst equation?
It is worth noting that the Nernst equation is a simplified approximation and does not take into account factors such as electrolytic resistance and tension distribution in the system.
How to calculate the voltage of an electrochemical system with the Nernst equation?
To calculate the voltage of an electrochemical system, it is necessary to know the values of E°, R, T, n, F and Q, and then use the formula E = E° − (RT/nF)·lnQ.
What is the equilibrium potential E°?
The equilibrium potential E° is the voltage of an electrochemical system when the concentrations of ions are equal on both sides of the membrane.