The membrane that surrounds a certain type of living cell has a surface area of 5.0 x 10-9 m2 and a thickness of 2.0 x 10-8 m. assume that the membrane behaves like a parallel plate capacitor and has a dielectric constant of 5.8. (a) the potential on the outer surface of the membrane is +58.5 mv greater than that on the inside surface. how much charge resides on the outer surface? (b) if the charge in part (a) is due to k+ ions (charge +e), how many such ions are present on the outer surface?