Consider an ion with charge +1 having intracellular concentration of 145 nM and extracellular concentration of 3 mM. Calculate the Nernst potential of this ion species in mV. Round your answer to one decimal place. Take Kbt = 4.1 x 10^-21 J/K and the fundamental charge of the electron e = -1.6 x 10^-19 C.
2. Suppose a cell's resting membrane potential is above -70 mV. The Nernst potential of Na+ in the system is about +60 mV with an intracellular concentration of about 15 mM and extracellular concentration of 145 mM. What is the reason the system is not in equilibrium?
a) There is a chemical driving force attempting to bring the Na+ ions inside the cell.
b) There is an electrical driving force attempting to bring Na+ ions inside the cell.
c) There is both a chemical and electrical driving force attempting to bring the Na+ ions inside the cell.
d) The system is in equilibrium since the Na+ ions are at their Nernst potential and are not moving across the membrane.