Consider the reaction represented by the following equation: N_2(g) + 3H_2(g) ⇌ 2NH_{3(g); ∆H^ϴ = -xkJ mol^-1. Which of the following conditions would increase the yield of NH3?}

• A Addition of iron catalyst
• B Increase in the temperature of the system
• C Increase in the volume occupied by reactants
• D Increase in the total pressure of the system