Given the Following Thermochemical Data at 25°C and 1 Atm

Multiple Choice

Given the following thermochemical data at 25°C and 1 atm pressure, O₂(g) + 2B(s) → B₂O₃(s) ; ΔH° = -1264 kJ
O₃(g) + 2B(s) → B₂O₃(s) ; ΔH° = -1406 kJ
Determine ΔH° for the following reaction at 25°C and 1 atm pressure.
3O₂(g) → 2O₃(g)

A) -980 kJ/mol
B) +284 kJ/mol
C) +980 kJ/mol
D) -2670 kJ/mol
E) -284 kJ/mol