Can someone explain the Nernst equation

[polarmolar]

Can someone explain the Nernst equation, thank you!!

---

Members don't see this ad.

 

[Tina324]

yes can someone? i just hope we don't need to know it...i skipped it in my studying😛

 

[doc3232]

Do we actually have to know this? The equation has about 10 variables in it...

 

[polarmolar]

I hope so too!

Its so weird because in one place Kaplan has it written with a "log" and the other with "ln" ....?

 

[drm85]

As a broad overview:

It is typically used to calculate the resting membrane potential (voltage) of a cell. In excitable cells there are two principle forces in play, concentration and electrical charge. The nernst takes both into account.

By taking the natural log (ln) of a given positive ion concentration outside divided by inside (opposite for chloride or neg charged ions) and multiplying that number by the gas constant R and the absolute temperature in kelvins and then dividing by the faraday constant. If the ion is negative then also divide by negative 1. Answers are typically expressed in mV.