| EK = |
RT | ln | [K+]out |
| zF | [K+]in |
where
| EK | The electric potential across the membrane due to the
potassium concentration gradient |
| R |
Universal gas constant (8.314472 J · K-1) |
| T | Absolute temperature (Kelvin = 273.15 + ºC = 298.15) at 25ºC |
| [K+]out | potassium concentration outside membrane |
| [K+]in | potassium concentration inside membrane |
| zF | Number of electric charges carried by a mole of K+ |
| z | Number of electrons (one for K+) |
| F | Faraday constant, equal to 9.6485309×104 C mol-1 |
Putting values in the equation gives this result. Try changing the values in the text fields and clicking the update button to compute a new value for EK (values in formula will be updated).