We’re being asked to determine the equilibrium constant (K) at 25 ˚C for the given reaction:
N2 (g) + 3H2 (g) → 2NH3 (g)
Recall that ΔG˚rxn and K are related to each other:
We can use the following equation to solve for ΔG˚rxn:
We can get the value of the ΔH˚rxn and ΔS˚rxn of the reaction from the textbook or the internet.
ΔH˚rxn = -93 kJ/mol
ΔS˚rxn = -198 J/K•mol
For this problem, we need to do the following steps:
Step 1: Use ΔH˚rxn and ΔS˚rxn to calculate for ΔG˚rxn.
Step 2: Calculate for K.
The Haber process is the principal industrial route for converting nitrogen into ammonia:
N2 (g) + 3H2 (g) → 2NH3 (g).
Using the thermodynamic data in Appendix C in the textbook, calculate the equilibrium constant for the process at room temperature.