To calculate the amount of energy required to boil 500g of water starting from 25C, we need to consider two steps:1. Heating the water from 25C to 100C the boiling point 2. Vaporizing the water at 100CFirst, let's calculate the energy required to heat the water from 25C to 100C. We will use the specific heat capacity of water, which is 4.18 J/gC.q1 = mass specific heat capacity Tq1 = 500g 4.18 J/gC 100C - 25C q1 = 500g 4.18 J/gC 75Cq1 = 156750 JNow, let's calculate the energy required to vaporize the water at 100C. We will use the enthalpy of vaporization of water, which is 40.7 kJ/mol. First, we need to convert the mass of water to moles.Molar mass of water H2O = 18.015 g/molmoles of water = mass / molar massmoles of water = 500g / 18.015 g/molmoles of water 27.75 molNow, we can calculate the energy required to vaporize the water.q2 = moles enthalpy of vaporizationq2 = 27.75 mol 40.7 kJ/molq2 1129.425 kJTo find the total energy required, we need to add the energy required for both steps. Since q1 is in J and q2 is in kJ, we need to convert q1 to kJ.q1 = 156750 J 1 kJ / 1000 J = 156.75 kJTotal energy required q_total = q1 + q2q_total = 156.75 kJ + 1129.425 kJq_total 1286.175 kJSo, the amount of energy required to boil 500g of water starting from 25C is approximately 1286.175 kJ.