If the 0.05 molar solution of M^+ is replaced by a 0.0025 molar M^+ solution, then the magnitude of — Electrochemistry Chemistry Question

💡 Solution & Explanation

The potential of a concentration cell depends on the natural log of the concentration ratio: E = (RT/nF) × ln(C2/C1). Initially, the ratio C2/C1 = 1 / 0.05 = 20, which gives E = 70 mV. In the second case, the new ratio is C2/C1' = 1 / 0.0025 = 400. Since 400 = 20^2, ln(400) = 2 × ln(20). This doubles the original cell potential. E_new = 2 × 70 mV = 140 mV. Therefore, correct answer is C.