The efficiency of an electrochemical cell can be calculated using the following formula:Efficiency = Actual cell voltage / Maximum possible cell voltage 100%In this case, the actual cell voltage is given as 1.8V, and the electrode potential is +0.6V. Since there are two electrodes in an electrochemical cell, the maximum possible cell voltage would be the sum of the potentials of both electrodes.Maximum possible cell voltage = 2 0.6V = 1.2VNow, we can calculate the efficiency:Efficiency = 1.8V / 1.2V 100% = 1.5 100% = 150%However, this result indicates that the efficiency is greater than 100%, which is not possible for any real system. There might be an error in the given data or a misunderstanding of the problem. Please recheck the values and the context of the problem.