THERMODYNAMICS: Use the given standard enthalpies of formation to calculate the AH° (in kJ) for the hypothetical reaction: (Round off the final answer to ONE decimal place. Do not include the unit.)...

Extracted text: THERMODYNAMICS: Use the given standard enthalpies of formation to calculate the AH° (in kJ) for the hypothetical reaction: (Round off the final answer to ONE decimal place. Do not include the unit.) 2X2D (g) + 3M2 (g) – 2X2M (I) + 2DM2 (g) AH°f for X2D (g) = -27.7 kJ/mol AH°; for DM2 (g) = -297.3 kJ/mol AH°f for X2M (1) = -280.8 kJ/mol AH°f for M2 (g) = 0 kJ/mol