Three enthalpy changes were measured at 298 K:
(1) C(s, graphite) + ½ O2(g) → CO(g) ΔH° = –110.5 kJ mol⁻¹
(2) CO(g) + ½ O2(g) → CO2(g) ΔH° = –283.0 kJ mol⁻¹
(3) C(s, graphite) + O2(g) → CO2(g) ΔH° = ?
Answer the questions that follow.
(a) Write a single algebraic combination of reactions (1) and (2) that produces reaction (3). Clearly indicate how each step is used.
(b) Determine ΔH° for reaction (3), showing all work and including the correct units.