Final answer:
The Nernst potential for potassium (K+) given an intracellular concentration of 150 mM and an extracellular concentration of 2 mM is approximately +115.31 mV.
Step-by-step explanation:
To calculate the Nernst potential for potassium (K+) under the provided conditions, we use the Nernst equation which relates the concentrations of the ion on both sides of the membrane:
EK = (RT / zF) * ln([Kout] / [Kin])
At body temperature (25°C or 298K), this simplifies to:
EK = -61.5 mV * log([Kout] / [Kin])
Given the intracellular concentration of K+ is 150 mM and the extracellular concentration is 2 mM, the equation becomes:
EK = -61.5 mV * log(2 / 150)
Upon calculating, we find:
EK = -61.5 mV * log(0.0133)
EK = -61.5 mV * (-1.875)
EK = +115.31 mV
Therefore, the Nernst potential for K+ under the given conditions is approximately +115.31 mV.