Change in Temperature Effect on Reaction

[Chiara Frank]

Hi guys! In section 5J of the textbook, problem 13 gives us a gaseous mixture that is heated to 600 K and allowed to reach equilibrium. We are asked if more ammonia be formed if that equilibrium mixture is then heated to 700 K? Considering the given equilibrium constants at each temperature, I understand that the constant for the formation of ammonia is smaller at the higher temperature, and the answer key explains that because of this, raising the temperature will favor the formation of reactants. However, when I think about this, if the equilibrium constant is smaller, wouldn't that mean that the concentration of reactants is higher than the products, and thus the reaction would shift toward the products following Le Chatelier's Principle? Would anyone be able to give me insight into this? Thank you!

[Christine Lin 1H]

Hi Chiara - I think you may gain some insight in why the formation of ammonia is smaller at the higher temperatures by comparing the K values at 600K (K=1.7x10^-3) vs at 700K(K=7.8x10^-5). Since the equilibrium constant at 700K is less than the equilibrium constant at 600K (closer to K=1), less ammonia will form than at 600K.

Hope this helps!