課程名稱︰物理化學
課程性質︰必修
課程教師︰陳立仁
開課學院：工學院
開課系所︰化工系
考試日期（年月日）︰2012/5/3
考試時限（分鐘）：60
是否需發放獎勵金：是
（如未明確表示，則不予發放）
試題 :
Problem 1 (25%)
The following data relate to an enzyme-catalyzed reaction.
10^3 [S]/mol dm^3 Rate, v/mol dm^3 s^-1
0.4 2.41
0.6 3.33
1.0 4.78
1.5 6.17
2.0 7.41
3.0 8.70
4.0 9.52
5.0 10.5
10.0 12.5
Calculate the Michaelis constant Km and the maxium rate V
Problem 2 (25%)
The reaction between iodide ions and the cobalt complex Co(CN)5OH2 2-, for
which the stoichiometric equation is
Co(CN)5OH2 2- + I- → Co(CN)5I 3- +H2O
Is believe to go by the mechanism
k1
Co(CN)5OH2 2- → Co(CN)5 2- + H2O
k2
Co(CN)5 2- + H2O → Co(CN)5OH2 2-
Co(CN)5 2- + I- → Co(CN)5I 3-
Assume that the intermediate exists in a steady state, and derive the general
rate equation. Write the rate equation for special cases of low and high
iodide concentration, and decide which is the rate-controlling step in each
case.
Problem 3 (25%)
The fokkowing is a slightly simplified version of the mechanism proposed in
1937 by G.K. Rollefson and R.F. Faull [JACS 59,625,1937] to explan the iodine-
catalyzed decomposition of acetaldehyde：
k1
I2 → 2I
k2
I + CH3CHO → HI + CH3CO
k3
CH3CO → CH3 + CO
k4
CH3 + HI → CH4 + I
k5
2I → I2
Apply the steady-state approximation to I, CH3CO and CH3 and obtain an
expression for the rate.
Problem 3 (25%)
Some enzyme reactions involving two substrates A and B occur by the following
mechanism.
k1
E+A→EA
k-1
EA→E+A
k2 k3
EA+B←→EAB→E+Y+Z
k-2
(This is known as the ordered ternary-complex mechanism; A must add first to E,
and the resulting complex EA reacts with B; the complex EB is not formed.)
The comcentrations of A and B are much larger than the concentration of E.
Apply the steady-state treatment and obtain an expression for the rate.
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 140.112.7.214