GKFix MCQ Question

What is the enthalpy change for the reaction: 2NH3(g) → N2(g) + 3H2(g)?

• A. +91.8 kJ mol⁻¹
• B. –91.8 kJ mol⁻¹
• C. +45.9 kJ mol⁻¹
• D. –45.9 kJ mol⁻¹