The following thermochemical equations are given at 298 K:
(1) C2H6(g) + 7/2 O2(g) → 2 CO2(g) + 3 H2O(l) ΔH = –1550.0 kJ
(2) C(graphite) + O2(g) → CO2(g) ΔH = –393.5 kJ
(3) H2(g) + 1/2 O2(g) → H2O(l) ΔH = –285.8 kJ
Using these data, calculate the enthalpy change, in kJ, for the synthesis reaction
2 C(graphite) + 3 H2(g) → C2H6(g),
and report your answer to the correct number of significant figures.