An ideal gaseous reaction (which is a hypothetical gaseous reaction that conforms to the laws governing gas behavior) occurs at a constant pressure of 30.0 atm and releases 72.6 kJ of heat. Before the reaction, the volume of the system was 7.40 L . After the reaction, the volume of the system was 2.00 L . Calculate the total internal energy change, ΔE, in kilojoules.