The value of ΔH° for the reaction 3 O2(g) ⇌ 2 O3(g) is +285 kJ. Does the equilibrium constant for this reaction increase or decrease when the temperature increases? Justify your answer using Le Châtelier’s principle.

Enthalpy, represented as ΔH°, is a measure of the total heat content of a system at constant pressure. A positive ΔH° indicates that the reaction is endothermic, meaning it absorbs heat from the surroundings. In the given reaction, the formation of ozone (O3) from oxygen (O2) requires energy, which is reflected in the positive value of +285 kJ.

Le Châtelier’s Principle states that if a dynamic equilibrium is disturbed by changing the conditions, the system will adjust to counteract the change and restore a new equilibrium. In the context of temperature changes, if the temperature is increased for an endothermic reaction, the system will shift to favor the formation of products to absorb the added heat, thereby increasing the equilibrium constant.

The equilibrium constant (K) quantifies the ratio of the concentrations of products to reactants at equilibrium for a given reaction at a specific temperature. For the reaction 3 O2(g) ⇌ 2 O3(g), an increase in temperature shifts the equilibrium towards the products (O3) due to the endothermic nature of the reaction, resulting in a higher value of K as the concentration of O3 increases relative to O2.