To calculate the enthalpy of solution of sodium hydroxide NaOH in water, we need to determine the amount of heat absorbed per mole of NaOH dissolved. We are given the heat absorbed by the solution 128.0 kJ/mol and the molar concentration of the solution 0.1 M .First, let's determine the amount of heat absorbed when 1 mole of NaOH is dissolved in water. We know that the heat absorbed by the solution is 128.0 kJ/mol, so:q = 128.0 kJ/molNow, we need to find the mass of the solution. Since the molar concentration of the solution is 0.1 M, this means that there are 0.1 moles of NaOH in 1 L 1000 mL of the solution. The density of the solution is 1.00 g/mL, so the mass of 1 L of the solution is:mass = density volumemass = 1.00 g/mL 1000 mLmass = 1000 gNow, we can calculate the change in temperature T of the solution using the heat absorbed q , the mass of the solution m , and the specific heat capacity of the solution Cp :q = m Cp TRearranging the equation to solve for T:T = q / m Cp Substituting the given values:T = 128,000 J / 1000 g 4.18 J/gK T = 128,000 J / 4180 J/KT = 30.62 KNow that we have the change in temperature, we can calculate the enthalpy of solution H using the heat absorbed q and the moles of NaOH dissolved:H = q / moles of NaOHSince there are 0.1 moles of NaOH in 1 L of the solution:H = 128,000 J / 0.1 molH = 1,280,000 J/molConverting to kJ/mol:H = 1,280 kJ/molTherefore, the enthalpy of solution of sodium hydroxide NaOH in water is 1,280 kJ/mol.