課程名稱︰物理化學二
課程性質︰必修
課程教師︰吳嘉文
開課學院：工
開課系所︰化工系
考試日期（年月日）︰2009/06/15
考試時限（分鐘）：110
是否需發放獎勵金：是
（如未明確表示，則不予發放）
試題 :
Final Exam of Physical Chemistry
June 15, 2009
1. (12%)
(a) Write the overall chemical equation and the cell notation for the
electrochemical cell shown below. (4%)
(b) You are given the following reduction reactions and Eo values:
Fe3+(aq) + e- -> Fe2+(aq) Eo = +0.771 V
Fe2+(aq) + 2e- -> Fe (s) Eo = -0.447 V
Calculate Eo for the electrochemical cell described in (a). (4%)
(c) Using the give data in (b) and calculate Eo for the half-cell reaction of
Fe3+(aq) + 3e- -> Fe (s). (4%)
2. (8%) Given E’ = 0.08 V for the Fe3+(cyt b)/Fe2+(cyt b) couple and E’ =
0.22 Vfor the Fe3+(cyt c1)/Fe2+(cyt c1) couple, where E’ represent the
standard-statereduction potentials at pH = 7.0 at 25 °C and cyt is an
abbreviation for cytochromes. Determine E’ and equilibrium constant (K)
for the equation
Fe3+(cyt c1) + Fe2+(cyt b) -> Fe2+(cyt c1) + Fe3+(cyt b)
3. (13%)
(a) Two solutions 1 dm3 in volume are separated by a membrane 1 dm2 in
area (A) and 0.1 cm in thickness (l), and this membrane is permeable to
K+ and Cl- ions but not to P- ions. The initial concentrations are shown
below. Calculate the concentrations on each side of the membrane after
equilibrium has become established. (4%)
(b) Define the Nernst potential. Calculate the Nernst potential across the
membrane if the temperature is 37 °C. (5%)
(c) Calculate the number of ions required to produce the Nernt potential in
(d). Assume the dielectric constant in vacuum is 8.854 x 10-12 (C2N-1m-2),
and the dielectric constant of the membrane is 3. (4%)
4. (10%) Use the following data for the cell
to determine the standard reduction potential for the AgCl/Ag couple.
m (mol kg-1) 0.00321 0.00448 0.00561 0.00731 0.00913 0.01119 0.01340
E (V) 0.52070 0.50401 0.49274 0.47965 0.46877 0.45878 0.44991
5. (10%) Describe electrochemical cells. (Principle, advantages, current
research
challenge, etc.) (Choose two from the following three cells, each one is 5%)
(a) Fuel cells
(b) Photogalvanic cells (or Dye-sensitized solar cells)
(c) Lithium ion batteries
6. (8%) The reaction
cis-Cr(en)2(OH)2+ trans-Cr(en)2(OH)2+
is first order in both direction. At 25 °C the equilibrium constant is 0.16
and the rate constant k1 is 3.3 x 10-4 s-1. In an experiment starting with
the pure cis form, how long would it take for half the equilibrium amount of
the trans isomer to be formed?
7. (10%) Derive the integrated rate equation and half-life (t1/2) for an
irreversible reaction of stoichiometry 2A + B -> Z. Assume the rate is
proportional to [A]2[B] and the reactants present in stoichiometric
proportions; take the initial concentration of A as 2a0 and that of B as
a0. (hint: t = 0, [Z] = 0; t = t, [Z] = x)
8. (12%) The following data have been obtained for the hydrolysis of adenosine
triphosphate, catalyzed by hydrogen ions:
Temp (°C) Rate constant k, (s-1)
39.9 4.67 x 10-6
43.8 7.22 x 10-6
47.1 10.0 x 10-6
50.2 13.9 x 10-6
Assume the Arrhenius equation can be applied. Calculate at 40 °C, the energy
of activation, the Gibbs energy of activation, the enthalpy of activation, and
the preexponential factor. (each one is 3%)
9. (8%) The reaction 2NO + O2 -> 2NO2 is believed to occur by the mechanism
Assume N2O2 to be in a steady state and derive the rate equation. Under what
conditions does the rate equation reduce to second-order kinetics in NO and
first-order kinetics in O2?
10. (9%) The following data apply to an enzyme-catalyzed reaction:
Substrate [S] (mol dm-3) Rate v, (mol dm-3 s-1)
2.5x10-4 2.3 x 10-4
5.0x10-3 7.8 x 10-4
The concentration of the enzyme is 3 g dm-3 and its molecular weight is 60000.
Assume the Michaelis-Menten equation to apply and calculate the Michaelis
constant Km, the limiting rate V, and the rate coefficient k2. (each one is
3%)
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