1. Using the Nernst equation, calculate the equilibrium potential for Ca21 and for Cl2 from the following sets of data: a. Given [Ca21]o 5 1 mM, [Ca21]i 5 100 nM, find ECa21 b. Given [Cl2]o 5 110 mM, [Cl2]i 5 10 mM, find ECl2

Answer : The value of and

Explanation :

To calculate the equilibrium potential we are using Nernst equation:

where,

 = equilibrium potential

z = valency of ion

= concentration of the ion outside the cell

= concentration of the ion inside the cell

Part a :

Given:

z = valency of ion = 2

= concentration of the ion outside the cell = 1 mM

= concentration of the ion inside the cell = 100 mM

Part b :

Given:

z = valency of ion = 1

= concentration of the ion outside the cell = 110 mM

= concentration of the ion inside the cell = 10 mM