To calculate the minimum amount of energy required to break H2O molecules in a system consisting of 100 water molecules at a temperature of 298 K, we will use the concept of Gibbs free energy. The Gibbs free energy G is the maximum amount of non-expansion work that can be extracted from a thermodynamic system at a constant temperature and pressure.The Gibbs free energy change G for a reaction can be calculated using the equation:G = H - TSwhere H is the change in enthalpy heat content , T is the temperature in Kelvin, and S is the change in entropy a measure of disorder .For the dissociation of water, the reaction can be written as:H2O l H2 g + 1/2 O2 g The standard enthalpy change H and standard entropy change S for this reaction can be found in thermodynamic tables:H = +285.8 kJ/molS = +163.3 J/molKNow, we can calculate the standard Gibbs free energy change G for the reaction at 298 K:G = H - TSG = 285.8 kJ/mol - 298 K 0.1633 kJ/molK G = 285.8 kJ/mol - 48.7 kJ/molG = 237.1 kJ/molThis is the Gibbs free energy change for breaking one mole of water molecules. Since we have 100 water molecules, we need to convert this value to the energy required for breaking 100 water molecules:Number of moles of water = 100 molecules / 6.022 x 10^23 molecules/mol 1.66 x 10^-22 molEnergy required = G x number of molesEnergy required = 237.1 kJ/mol x 1.66 x 10^-22 mol Energy required 3.94 x 10^-20 kJTherefore, the minimum amount of energy required to break 100 H2O molecules in a system at a temperature of 298 K is approximately 3.94 x 10^-20 kJ.