Enthalpy and Entropy Contributions to K (18.4.1)

Question 1

• The standard Gibbs free energy change of reaction (∆G°) is related to the equilibrium constant (Keq).

Answer 1

• The standard Gibbs free energy change of reaction (∆G°) is related to the equilibrium constant (Keq).

Question 2

• The equilibrium constant is related to both the ∆H° and the ∆S° in the following way: ln Keq = ∆H°/(RT) + ∆S°/R

Answer 2

• The equilibrium constant is related to both the ∆H° and the ∆S° in the following way: ln Keq = ∆H°/(RT) + ∆S°/R

Question 3

• At high temperatures, ∆S° determines whether ∆G° is positive or negative; at low temperatures, ∆H° determines whether ∆G° is positive or negative.

Answer 3

• At high temperatures, ∆S° determines whether ∆G° is positive or negative; at low temperatures, ∆H° determines whether ∆G° is positive or negative.