A constant-volume calorimeter was calibrated by carrying out a reaction known to release 3.50 kJ of heat in 0.200 L of solution in the calorimeter (q = –3.50 kJ), resulting in a temperature rise of 7.32°C. In a subsequent experiment, 100.0 mL of 0.200 m HBr(aq) and 100.0 mL of 0.200 m KOH(aq) were mixed in the same calorimeter and the temperature rose by 2.49°C. What is the change in the internal energy of the reaction mixture as a result of the neutralization reaction?