At what temperature does the following reaction become spontaneous?

Question

At what temperature does the following reaction become spontaneous?

You may assume that ΔHº and Sº are temperature independent.

2NO (g) + 2H₂(g) --> N₂(g) + 2H₂O (g)

Answer 1

We will need more thermodynamic information, such as ∆H and ∆S, or at least values for formation of reactants and products, so that we can calculate ∆H and ∆S.

If you have such values, you can determine the temperature at which the reaction becomes spontaneous by

∆G = ∆H - T∆S

Reaction will be spontaneous when ∆G = 0 (or becomes negative), so set ∆G = 0 and plug in the values for ∆H and ∆S and solve for T. That will give you the temperature in Kelvin at which the reaction is spontaneous.