First, we need to determine the amount of heat released during the reaction. We can do this using the formula:q = mcTwhere q is the heat released, m is the mass of the solution, c is the specific heat capacity, and T is the change in temperature.Since the density of the solution is not given, we will assume it is approximately equal to the density of water, which is 1 g/mL. Therefore, the mass of the 50 mL solution is:m = 50 mL * 1 g/mL = 50 gNow we can calculate the heat released:q = 50 g 4.18 J/gK -10C = -2090 JThe heat released is negative because the reaction is exothermic the temperature decreased .Next, we need to determine the moles of magnesium reacting. The molar mass of magnesium is 24.31 g/mol. So, the moles of magnesium in 1 g of magnesium powder are:moles of Mg = 1 g / 24.31 g/mol = 0.0411 molNow we can calculate the enthalpy of ionization of magnesium. The enthalpy of ionization is the heat released per mole of magnesium ionized. We can find this by dividing the heat released by the moles of magnesium:H_ionization = q / moles of Mg = -2090 J / 0.0411 mol = -50800 J/molThe enthalpy of ionization of magnesium is -50.8 kJ/mol.