142. Solving a chemistry problem

9.8. Calculate e ´if it is known that the flow potential determined by forcing a potassium chloride solution through a corundum diaphragm under a pressure of 20 · 10 ^ 3 Pa is 22.5 · 10–3 V.
The specific conductivity of the solution is Xv = 1.37 · 10–2 Ohm – 1 · m – 1, the diaphragm efficiency coefficient is a = 1.8; e is 81; n = 1 · 10–3 Pa · s.