A cell has the following concentration of ions inside and ou

A cell has the following concentration of ions inside and outside the cell membrane which is permeable to these ions: W hat potential difference would be recorded between the cell interior and exterior?

Solution

potential difference calculation using Nernst equation-

E = 2.3 RT/zF log C₁/ C₂. ( 2.3 RT/zF = constant. its value at 37^o C is approx 60 mV).

here-

E= equilibrium potential.

R= universal gas constant. (2 Cal Mol^-1 K^-1).

T= temperature in Kelvin.

F= faraday constant.

z= charge on ion.

C= concentration of ion.

Now equilibration potential for Cl^- ion-

=60mV/1 *log₁₀ 100/40.

=60mV *0.4 = 24 mV ( or -24 mV, inside negative).

equilibration potential for Na⁺ ion-

=60mV/1 *log₁₀ 100/10.

=60mV * 1 = 60 mV ( or +60 mV, inside positive).

equilibration potential for K⁺ ion-

=60mV/1 *log₁₀ 150/15.

=60mV * 1 = 60 mV ( or -60 mV, inside negative).