Standard enthalpy of reaction requires all formation enthalpies

Steps:

• Identify the formula: ΔH°_rxn = [ΔH°_f(N₂O(g)) + 2ΔH°_f(H₂O(g))] - ΔH°_f(NH₄NO₃(s)).
• Substitute known values: ΔH°_f(NH₄NO₃(s)) = 50.6 kJ mol⁻¹; 2ΔH°_f(H₂O(g)) = 2(-214) = -428 kJ mol⁻¹.
• Note ΔH°_f(N₂O(g)) is required but not provided in the data.
• Without ΔH°_f(N₂O(g)), the calculation cannot be completed.

Not enough information.

Final answer: Not enough information.