Search results
Results From The WOW.Com Content Network
The equilibrium potential for an ion is the membrane potential at which there is no net movement of the ion. [1] [2] [3] The flow of any inorganic ion, such as Na + or K +, through an ion channel (since membranes are normally impermeable to ions) is driven by the electrochemical gradient for that ion.
In electrochemistry, the Nernst equation is a chemical thermodynamical relationship that permits the calculation of the reduction potential of a reaction (half-cell or full cell reaction) from the standard electrode potential, absolute temperature, the number of electrons involved in the redox reaction, and activities (often approximated by concentrations) of the chemical species undergoing ...
[1] [2] At chemical equilibrium or in phase equilibrium, the total sum of the product of chemical potentials and stoichiometric coefficients is zero, as the free energy is at a minimum. [3] [4] [5] In a system in diffusion equilibrium, the chemical potential of any chemical species is uniformly the same everywhere throughout the system. [6]
Goldman-Hodgkin-Katz Equation Calculator; Nernst/Goldman interactive Java applet The membrane voltage is calculated interactively as the number of ions are changed between the inside and outside of the cell. Potential, Impedance, and Rectification in Membranes by Goldman (1943)
The reversal potential (or equilibrium potential) of an ion is the value of transmembrane voltage at which diffusive and electrical forces counterbalance, so that there is no net ion flow across the membrane. This means that the transmembrane voltage exactly opposes the force of diffusion of the ion, such that the net current of the ion across ...
In other words, the exchange current density is the rate of reaction at the reversible potential (when the overpotential is zero by definition). At the reversible potential, the reaction is in equilibrium meaning that the forward and reverse reactions progress at the same rates. This rate is the exchange current density.
You can calculate E assuming an outside concentration, [K +] o, of 10mM and an inside concentration, [K +] i, of 100mM. For chloride ions (Cl −) the sign of the constant must be reversed (−61.54 mV). If calculating the equilibrium potential for calcium (Ca 2+) the 2+ charge halves the
They can be better interpreted as the potential to perform "useful work", and the potential can be wasted. [7] Thermodynamic potentials are very useful when calculating the equilibrium results of a chemical reaction, or when measuring the properties of materials in a chemical reaction. The chemical reactions usually take place under some ...