An example of a homogeneous reversible reaction is the reaction between hydrogen and iodine. H2(g) I2(g) s 2HI(g) (a) Outline the characteristics of a homogeneous chemical system that is in a state of equilibrium. (2) (b) Deduce the expression for the equilibrium constant, Kc. (1) (c) Predict what would happen to the position of equilibrium if the pressure is increased from 1 atm to 2 atm. (1) (d) The value of Kc at 500 K is 160 and the value of Kc at 700 K is 54. Deduce what this information tells us about the enthalpy change of the forward reaction. (1) (e) The reaction can be catalysed by adding platinum metal. State and explain what effect the addition of platinum would have on the value of the equilibrium constant.