50.0 mL of 1.0 M HCl at 25.0 oC were mixed with 50.0 mL of 1.0 M NaOH also at 25.0 oC in a styrofoam cup calorimeter. After the mixing process, the thermometer reading was at 31.9 oC. Calculate the energy involved in the reaction and the enthalpy per moles of hydrogen ions used.