The reaction of iron and water vapor results in an equilibrium 3/4 Fe(s) H2O(g) ? 1/4 Fe3O4(s) H2(g) and an equilibrium constant, Kp of 5.3 at a given temperature. What is the partial pressure of water present at equilibrium, if the reaction is initiated in a 26 L container with a partial pressure of H2 equal to 14.5 atm and excess iron oxide, Fe3O4.