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Heterogeneous Equilibria 1. What is meant by the following? a) Homogeneous Equilibrium b) Heterogeneous Equilibrium 2. Dddd The concentrations of pure solids, pure liquids, and solvents are omitted from equilibrium constant expressions because they do not change significantly during reactions when enough is present to reach equilibrium. 3. jjj Write each expression for KK, incorporating all constants, and KpKp for the following equilibrium reactions. a. PCl3(l)+Cl2(g)⇌PCl5(s)PCl3(l)+Cl2(g)⇌PCl5(s) b. Fe3O4(s)+4H2(g)⇌3Fe(s)+4H2O(g)Fe3O4(s)+4H2(g)⇌3Fe(s)+4H2O(g) Given: balanced equilibrium equations Asked for: expressions for KK and KpKp Strategy: Find KK by writing each equilibrium constant expression as the ratio of the concentrations of the products and reactants, each raised to its coefficient in the chemical equation. Then express KpKp as the ratio of the partial pressures of the products and reactants, each also raised to its coefficient in the chemical equation. Solution: This reaction contains a pure solid (PCl5PCl5) and a pure liquid (PCl3PCl3). Their concentrations do not appear in the equilibrium constant expression because they do not change significantly. So K=1[Cl2]K=1[Cl2] and Kp=1PCl2Kp=1PCl2 This reaction contains two pure solids (Fe3O4Fe3O4 and FeFe), which do not appear in the equilibrium constant expressions. The two gases do, however, appear in the expressions: K=[H2O]4[H2]4K=[H2O]4[H2]4 and Kp=(PH2O)4(PH2)4