\[\Delta\mu=RT\ln\left(\frac{C_2}{C_1}\right)+zF\Delta V\]
Variables
dmuelectrochemical potential difference (J/mol)
Runiversal gas constant (J/mol·K)
Tabsolute temperature (K)
C1initial concentration
C2final concentration
zionic charge number
FFaraday constant (C/mol)
dVelectric potential difference (V)
Description
What is this formula?
This formula calculates the electrochemical potential difference of an ion considering both concentration gradients and electrical potential differences across a membrane.
When to use it
Use this formula in biophysics, electrochemistry, neuroscience, or membrane transport analysis when studying ionic movement across membranes.
Example
An ion experiences:
C1=10 mol/m³
C2=100 mol/m³
z=1
dV=-0.07 V
T=310 K
Constants:
R=8.314 J/mol·K
F=96485 C/mol
Formula:
dmu=R*T*ln(C2/C1)+(z*F*dV)
Substitution:
dmu=8.314*310*ln(100/10)+(1*96485*(-0.07))
Result:
dmu≈-829 J/mol
The ion experiences a net electrochemical driving force of approximately -829 J/mol.
Applications
- Ion transport analysis
- Cellular membrane studies
- Electrochemical systems
- Neuron electrophysiology
- Bioenergetics