To calculate the efficiency of the electrochemical cell, we first need to determine the electrical work done by the cell and then compare it to the total energy consumed.1. Calculate the electrical work done W using the formula: W = V * I * t, where V is the potential difference, I is the current, and t is the time.V = 1.5 VI = 1.5 At = 2 hours = 2 * 3600 seconds = 7200 secondsW = 1.5 V * 1.5 A * 7200 s = 16200 Joules2. Calculate the efficiency using the formula: = Electrical work done / Total energy consumed * 100 = 16200 J / 5400 J * 100 = 3 * 100 = 300%However, the efficiency cannot be greater than 100%. This indicates that there might be an error in the given data or the calculation. Please double-check the provided information.