Which of the following reactions is associated with the definition of K„? O Zn(OH2),²*(aq) = (Zn(OH2);OH]*(aq) + H*(aq) CN (ag) + H*(aq) = HCN(aq) O Cr**(aq) + 6H20(1) = Cr(OH2)6*(aq) none of these O F (aq) + H2O(!) = HF(aq) + OH (aq)

Calculate the value of the equilibrium constant for the reaction N2(g)+2O2(g)2NO2(g) if the concentrations of the species at equilibrium are [N2] = 0.0013, [O2] = 0.0024, and [NO2] = 0.00065.

The following question is taken from a Chemistry Advanced Placement Examination and is used with the permission of the Educational Testing Service. Solve the following problem: MgF2(s)Mg2+(aq)+2F(aq) In a saturated solution of MgF2 at 18 C, the concentration of Mg2+ is 1.21103M . The equilibrium is represented by the preceding equation. (a) Write the expression for the solubility-product constant, Ksp, and calculate its value at 18 C. (b) Calculate the equilibrium concentration of Mg2+ in 1.000 L of saturated MgF2 solution at 18 C to which 0.100 mol of solid KF has been added. The KF dissolves completely. Assume the volume change is negligible. (c) Predict whether a precipitate of MgF2 will form when 100.0 mL of a 3.00103 -M solution of Mg(NO3)2 is mixed with 200.0 mL of a .2.00103 -M solution of NaF at 18 C. Show the calculations to support your prediction.. (d) At 27 C the concentration of Mg2+ in a saturated solution of MgF2 is 1.17103M . Is the dissolving of MgF2 in water all endothermic or an exothermic process? Give an explanation to support your conclusion.

In a particular experiment, the equilibrium constant measured for the reaction, Cl2(g)+NO2(g)Cl2NO2(g), is 2.8. Based on this measurement, calculate AG° for this reaction. Calculate AG° using data from Appendix E at the back of the book and discuss the agreement between your two calculations.