The standard heat of reaction for the combustion of liquid n-nonane to form CO2 and liquid water at 25 C and 1 atm is Hr^ = -6124 kJ/mole. The reaction is:

1. Exothermic, and the reactor should be heated.

2. Exothermic, and the reactor should be cooled.

3. Endothermic, and the reactor should be heated.

4. Endothermic, and the reactor should be cooled.