CHEMISTRY COMMUNITY

A gaseous mixture consisting of 2.23 mmol N2 and 6.69
mmol H2 in a 500.-mL container was heated to 600. K and
allowed to reach equilibrium. Will more ammonia be formed if
that equilibrium mixture is then heated to 700. K?

How would we do this problem if we didn't know that this reaction is exothermic?

You can compare the equilibrium constants of this reaction under different temperatures to see whether the reaction is exothermic or endothermic. If the equilibrium constant in the lower temperature is higher than the equilibrium constant in the higher temperature, the reaction is exothermic. The opposite result will make this reaction endothermic.

The problem also tells you that K=7.8*10^-5 at 700K which is less than K at 600K. Therefore more ammonia (the product) would be formed at 600K since a greater K value means a greater ratio of products to reactants.