To calculate the heat of crystallization of NaOH, we first need to determine the moles of NaOH dissolved in water.The molar mass of NaOH is:Na = 22.99 g/molO = 16.00 g/molH = 1.01 g/molNaOH = 22.99 + 16.00 + 1.01 = 40.00 g/molNow, we can calculate the moles of NaOH:moles = mass / molar massmoles = 25g / 40.00 g/mol = 0.625 molThe heat released when 25g of NaOH dissolves in 100g of water is given as 4.75 kJ. To find the heat of crystallization per mole, we will divide the heat released by the moles of NaOH:Heat of crystallization = heat released / moles of NaOHHeat of crystallization = 4.75 kJ / 0.625 mol = 7.6 kJ/molTherefore, the heat of crystallization of NaOH is 7.6 kJ/mol.