The enthalpy of combustion of sulfur to SO2 at 25 °C is –297 kJ. The conversion of SO2(g) to SO3(g) at the same conditions has an enthalpy change of –99 kJ mol⁻¹ of SO3 produced.
Determine the enthalpy change, in kJ, for the reaction
2 S(s) + 3 O2(g) → 2 SO3(g).