Ammonia is produced industrially via the Haber process:
N2(g) + 3 H2(g) → 2 NH3(g)
Selected average bond energies:
• N≡N 226 kcal mol⁻¹
• H–H 104 kcal mol⁻¹
• N–H 93 kcal mol⁻¹
(Conversion factor: 1 cal = 4.184 J.)
Complete all parts below, clearly indicating each step, showing unit conversions, and giving final answers in kJ mol⁻¹.
(a) Convert each bond energy in the table to kJ mol⁻¹.
(b) For one mole of reaction as written, determine the total energy required to break the reactant bonds and the total energy released in forming the product bonds.
(c) Calculate ΔH for the reaction in kJ mol⁻¹.
(d) Determine the enthalpy change per mole of NH3 produced and explain why large‐scale ammonia plants employ heat exchangers to recover energy from the reaction mixture.