Ch. 15  equilibrium I                test     [85 points]                               AP Chem

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1. A mixture of 0.200 mole of NO, 0.10 mole of H2 and 0.20 mole of water was placed in a 2.0 L vessel.  The following equilibrium is established:  2 NO(g) +  2 H2(g)  ↔  N2(g)  +  2 H2O(g).  At equilibrium, [NO] = 0.062 M.  [20 points; based on HW problem 15.17]

a.  Determine the equilibrium concentrations of H2, N2, and water.

b. What is the numerical value of the equilibrium constant, Kp, of the reaction at 37 ºC ?

2. If Kc = 10.0 for the reaction:  2 N2(g)  +  6 H2(g)  ↔  4 NH3(g), what is the numerical value for the reaction:  ____.  [15 points; similar to HW 15.19]

a.  N2(g)  +  3 H2(g)  ↔  2 NH3(g)

b.  6 NH3(g),  ↔  3 N2(g)  +  9 H2(g) 

c. Given the following hypothetical  (?) values of Kc for the reactions:

Glucose  +  ATP ↔  glucose-6-phosphate  +  ADP                                        K1 = 10.0

Glucose-6-phosphate ↔  fructose-6-phosphate                                              K2 = 0.5

Fructose-6-phosphate + ATP  ↔  fructose-1, 6-diphosphate + ATP              K3 = 3.0

Fructose-1, 6- diphosphate  ↔  2 glyceraldehyde 3-phosphate + dihydroxyacetone phosphate                                                                                                        K4 = 0.25

What is the value of Kc for the reaction: 

glucose + 2 ATP  ↔  fructose-1, 6-diphostate + 2 ADP

3. The Kc of the reaction, PCl5(g)  ↔   PCl3(g)  + Cl2(g), is 1.80.  The initial concentration of PCl5, PCl3, and Cl2 are 2.0 M, 4.0 M, and 6.0 M, respectively.  What is the equilibrium concentrations of all chemicals in the reaction ?  [15 points;  based on HW 15.37]

4. A step in glycolysis, Glucose-6-phosphate ↔  fructose-6-phosphate, has Δ Gº > 0, yet the reaction occurs; rationalize how the reaction could occur ?  [10 points; hint:  see # 2c]

6. In regards to the reaction:  NH3(g)  +  HCl(g)  ↔  NH4Cl(s) at equilibrium, what is the effect on the number of moles of NH3 due to ___; justify / rationalize your response.  [25 points]

a. The addition of solid ammonium chloride at constant temperature and volume.

b. The addition of He at constant temperature and pressure.

c.  Adding a catalyst to the system [hmm; did your read the textbook ?]

d. cooling the system