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1.
The kinetics of the mercury(II) catalysed ligand exchange of the hexacyanoferrate(II) complex with the N-methylpyrazinium ion (Mpz+) in a potassium hydrogen phthalate buffer medium has been investigated at 25.0 ± 0.1 °C, pH = 5.0 ± 0.02 and ionic strength, I = 0.1 M (KNO3). The reaction was followed spectrophotometrically in the aqueous medium by measuring the increase in absorbance of the intense blue complex [Fe(CN)5Mpz]2– at its max 655 nm. The effect of pH, and the concentrations of [Fe(CN)6
4–] and Mpz+ on the reaction rate have been studied and analysed. The varying catalytic activity of mercury(II) as a function of concentration has also been explained. The kinetic data suggest that substitution follows an interchange dissociative (I
d) mechanism and occurs via formation of a solvent-bound intermediate. The effects of the dielectric constant of the medium on the reaction rates have been used to visualize the formation of a polar activated complex and an interchange dissociative mechanism for the reaction. A mechanism has been proposed in order to interpret the kinetic data. Kinetic evidence is reported for the displacement of CN– by Mpz+ in [Fe(CN)6
4–]. Activation parameters for the catalysed and uncatalysed reaction have been evaluated, and lend further support to the proposed mechanism. 相似文献
2.
R. Fujiyoshi T. Arai M. Katayama 《Journal of Radioanalytical and Nuclear Chemistry》1994,185(1):133-143
Ligand exchange reaction of Zn(II)-acetylacetonate complex (Zn-acac2) with 5,10,15,20-tetraphenyl-21H,23H-porphinetetrasulfonic acid (H2TPPS) has been investigated spectrophotometrically and radiometrically. The exchange reaction was observed by spectral change from H2TPPS to Zn-TPPS or activity of65Zn(acac)2 extracted into the chloroform phase. The 2nd order rate constants (k
2) for the exchange reaction at 70 °C and at pH 7.8 were found to be 32.8±2.3 and 31.2±3.2 M–1·s–1 from the spectrometric and radiotracer experiments, respectively. For the direct complexation of Zn(II) with H2TPPS, a similar 2nd order rate constant (k=32.4±4.7 M–1·s–1) was obtained as that in the ligand exchange reaction. The activation energies (E) for the exchange and the formation of Zn-TPPS were found to be 69.3±0.2 and 69.4±0.2 kJ·mol–1, respectively, in the temperature range from 40 to 70 °C. 相似文献
3.
The complex formation reactions between iodine and DBzDA18C6, A15C5 and N‐phenylA15C5 have been studied spectrophotometrically in chloroform solution. In the case of DBzDA18C6 is the resulting 1:2 (ligand…I+)I3?, while, in the case of A15C5 and N‐phenylA15C5 a 2:2 molecular complex of [(ligand)2…I+]I3? type was formed. The spectrophotometric results indicate that gradual release of triiodide ion from its contact ion paired form in the molecular complex into the solution is the rate‐determining step of the reaction. The kinetic rate constants for the complexation reactions were determined at different temperatures, and activation parameters were calculated from Arrhenius and Eyring equations. 相似文献
4.
Enthalpies of dissolution of benzo-15-crown-5 ether (B15C5) in mixtures of acetonitrile with water and in solutions of NaI and NaBPh4 (I=0.05 mol dm–3) in these mixtures were measured at 298.15 K. From the obtained results and appropriate literature data, the thermodynamic functions of B15C5/Na+ complex formation in acetonitrile-water mixtures were determined. The enthalpies of transfer of the complex B15C5/Na+ from pure acetonitrile to the examined mixtures were calculated and are discussed. 相似文献
5.
Dušan Malešev Zorica Radović Milena Jelikić-Stankov 《Monatshefte für Chemie / Chemical Monthly》1991,122(6-7):429-434
Summary Investigations on the composition of the molybdate(II)-3-hydroxyflavone complex and its stability constant have been carried out in 70% ethanolic solutions at room temperature (20°C), in the presence of a buffer atpH 6.30±0.05 and ionic strength 0.015. It has been found that a complex [MoO3(C15H9O3)
2
2–
] whose stability constant ranges from 15.13 atpH 6.25 to 13.02 atpH 7.00 is formed. Conditions are given for the determination of 3-hydroxyflavone by means of the reaction of complex formation in 50% ethanol atpH 6.60±0.05 and an ionic strength of 0.0225.
Untersuchung des Molybdat(II)-3-hydroxyflavon-Komplexes
Zusammenfassung Die Untersuchungen der Zusammensetzung des Komplexes und seiner Stabilitätskonstante wurden in 70% Ethanol, bei Raumtemperatur (20°C), in Anwesenheit von Puffer beipH=6.30±0.05 und der Ionenstärke 0.015 ausgeführt. Es wird der Komplex [MoO3(C15H9O3) 2 2– ] gebildet, die Stabilitätskonstanten reichen von 15.13 beipH 6.25 bis zu 13.02 beipH 7.00. Es wurden die Bedingungen zur quantitativen Bestimmung von 3-Hydroxyflavon mittels des Molybdenkomplexes in 50% Ethanol, beipH=6.60±0.05 und der Ionenstärke 0.0225 ermittelt.相似文献
6.
The hydrolysis equilibrum of gallium (III) solutions in aqueous 1 mol-kg–1 NaCl over a range of low pH was measured potentiometrically with a hydrogen ion concentration cell at temperatures from 25 to 100°C at 25°C intervals. Potentials at temperatures above 100°C increased gradually because of further hydrolysis of the gallium(III) ion, followed by precipitation. The results were treated with a nonlinear least-squares computer program to determine the equilibrium constants for gallium(III)–hydroxo complexes using the Debye–Hückel equation. The log K (mol-kg–1) values of the first hydrolysis constant for the reaction, Ga3+ + H2O GaOH2+ + H+ were –2.85 ± 0.03 at 25°C, –2.36 ± 0.03 at 50°C, –1.98 ± 0.01 at 75°C, and –1.45 ± 0.02 at 100°C. The computed standard enthalpy and entropy changes for the hydrolysis reaction are presented over the range of experimental temperatures. 相似文献
7.
A. N. Chekhlov 《Russian Journal of Coordination Chemistry》2001,27(6):381-386
The crystal structure of triaqua(1,10-diaza-18-crown-6)chlorobarium chloride [Ba(DA18C6)Cl(H2O)3]+Cl–(I) is studied by X-ray diffraction analysis: space group Pnma, a= 14.912, b= 13.590, c= 10.456 Å, Z= 4. Structure Iis solved by the direct method and refined by the full-matrix least-squares method in the anisotropic approximation: R= 0.079 for all 3194 measured independent reflections (CAD-4 diffractometer, MoK
). Crystal Iexists as complex guest–host cations and Cl–anions connected via interionic hydrogen bonds. The cations and anions are located in the msymmetry plane. The Ba2+ion (coordination number 10) is in the cavity of the DA18C6 macrocycle and is coordinated by its six heteroatoms (2N + 4O) and also by the Cl–anion and two O atoms of two water molecules from one side of the macrocycle and by the O atom of the third water molecule from another side. The DA18C6 ligand in Ihas the conformation of a crown with an approximate D
3d
symmetry. 相似文献
8.
Kinetics of oxidation of pyruvic acid by [ethylenebis(biguanide)]silver(III) in aqueous acidic media
The oxidation of pyruvic acid by the title silver(III) complex in aqueous acidic (pH, 1.1–4.5) media is described. The reaction products are MeCO2H and CO2, together with a colourless solution of the Ag+ ion. The free ligand, ethylenebis(biguanide) is released in near-quantitative yield upon completion of the reduction. The parent complex, [Ag(H2L)]3+ and one of its conjugate bases, [Ag(HL)]2+, participate in the reaction with both pyruvic acid (HPy) and the pyruvate anion (Py–) as the reactive reducing species. Ag+ was found to be catalytically inactive. At 25.0°C, I=1.0moldm–3, rate constants for the reactions [Ag(H2L)]3++HPy (k
1), [Ag(H2L)]3++Py– (k
2), [Ag(HL)]2++HPy (k
3) and [Ag(HL)]2++Py– (k
4) arek
1=(94±6)×10–5dm3mol–1s–1, (k
2
K
a+k
3
K
a1)= (1.3±0.1)×10–5s–1 and k
4=(58±4)×10–5dm3mol–1s–1, respectively, where K
a1is the first acid dissociation constant of the [Ag(H2L)]3+ and K
a is for pyruvic acid. A comparison between the k
1 and k
4 values is indicative of the judgement that k
2k
3. A one-electron inner-sphere redox mechanism seems more justified than an outer-sphere electron-transfer between the redox partners. 相似文献
9.
In order to determine the ion-pair formation constant of a crown ether-metal salt 1:1:1 complex in water, an equation is derived from regular solution theory and its predictions are verified experimentally by the solvent extraction method using benzo-18-crown-6 (B18C6), potassium picrate (KA), and various diluents of low dielectric constant. The distribution constants of B18C6 itself and the overall extraction constants of KA with B18C6 were determined at 25±0.2°C. The distribution constants of the neutral K(B18C6)A complex were calculated from these data. The literature value for the complex-formation constant of K(B18C6)+ in water and the ion-pair formation constant (K
K(B18C6)A
) for K(B18C6)A in water determined in this study were log K
K(B18C6)A
=3.12±0.23 at 25°C). The distribution behavior of B18C6 and K(B18C6)A is explained in terms of regular solution theory. The molar volumes V (cm3·mol–1) and solubility parameters (cal1/2-cm–3/2) are as follows: V
B18C6
=249±36; V
K(B18C6)A
=407±56; B18C6 = 11.5 ± 0.5; and K(B18C6)A = 11.5 ± 0.5. 相似文献
10.
Summary The kinetics of formation and dissociation of the binuclear complex of CoII with histidinato(pentaammine)CoIII have been studied at 10.0°Ct°C25°C and I = 0.3 mol dm–3 (ClO
inf4
sup–
). The formation of the binuclear complex, [(NH3)5CoIIILCoII]4+ (L = histidinate), in the 5.7–6.8 pH range involves the reaction of Co(OH2)
inf6
sup2+
with the deprotonated, (NH3)5CoL2+, and monoprotonated, (NH3)5CoLH3+, forms of the complex. The rate and activation parameters for the formation are consistent with an I
d mechanism. The binuclear species undergoes dissociation to yield the parent CoIII substrate and Co(OH2)
inf6
sup2+
via spontaneous and acid-catalysed paths. Comparison of spontaneous dissociation rate of the binuclear complex with other related systems indicated the chelate nature of the binuclear species. 相似文献
11.
The thermal behaviour of Ba[Cu(C2O4)2(H2O)]·5H2O in N2 and in O2 has been examined using thermogravimetry (TG) and differential scanning calorimetry (DSC). The dehydration starts at relatively low temperatures (about 80°C), but continues until the onset of the decomposition (about 280°C). The decomposition takes place in two major stages (onsets 280 and 390°C). The mass of the intermediate after the first stage corresponded to the formation of barium oxalate and copper metal and, after the second stage, to the formation of barium carbonate and copper metal. The enthalpy for the dehydration was found to be 311±30 kJ mol–1 (or 52±5 kJ (mol of H2O)–1). The overall enthalpy change for the decomposition of Ba[Cu(C2O4)2] in N2 was estimated from the combined area of the peaks of the DSC curve as –347 kJ mol–1. The kinetics of the thermal dehydration and decomposition were studied using isothermal TG. The dehydration was strongly deceleratory and the -time curves could be described by the three dimensional diffusion (D3) model. The values of the activation energy and the pre-exponential factor for the dehydration were 125±4 kJ mol–1 and (1.38±0.08)×1015 min–1, respectively. The decomposition was complex, consisting of at least two concurrent processes. The decomposition was analysed in terms of two overlapping deceleratory processes. One process was fast and could be described by the contracting-geometry model withn=5. The other process was slow and could also be described by the contracting-geometry model, but withn=2.The values ofE
a andA were 206±23 kJ mol–1 and (2.2±0.5)×1019 min–1, respectively, for the fast process, and 259±37 kJ mol–1 and (6.3±1.8)×1023 min–1, respectively, for the slow process.Dedicated to Prof. Menachem Steinberg on the occasion of his 65th birthday 相似文献
12.
Nigamananda Das 《Transition Metal Chemistry》1993,18(4):372-376
Summary The kinetics of reversible complexation of Ni(OH2)
inf6
sup2+
with oxygen-bonded glycinatocobalt(III) substrates N4-Co(glyH)gly2+ [N4 = (en)2 or trien; glyH = H3N+CH2-COO–] have been investigated by the stopped-flow technique in the 20–35° C range, at pH = 6.08–6.82 and I = 0.3 mol dm–3. The formation of N4Co(glyH)glyNi4+ occurred via the reaction of Ni(OH2)
inf6
sup2+
with the deprotonated form of the cobalt(III) substrates, N4Co-(glyH)gly2+. The rate and activation parameters for the formation and dissociation of the binuclear species are reported. The formation rate constants k
f (at 25° C), activation enthalpy and entropy H
, S
for N4Co-(glyH)glyNi4+ are 320±49, 341 ± 52dm3mol–1 s–1, 78 ± 7, 79 ± 5 kJmol–1 and 64 ± 24, 69 ± 18 JK–1 mol–1 for the ethylenediamine and triethylenetetraminecobalt(III) substrates, respectively. This result indicates that the rate and activation parameters are virtually independent of the nature of N4 moities, which strongly suggests that the formation of mono-bonded species occurs via entry of one of the pendant NH2 groups into the coordination sphere of nickel(II) via a rate-limiting Ni-OH2 bond dissociation mechanism (Id). The binuclear species exist in dynamic equilibrium between the monodentate and chelated forms, with the chelate form predominating. The low values of spontaneous dissociation rate constant for the binuclear species (k
r- 0.095–1 at 25° C) in comparison with the high values of dissociation rate constants of monodentate nickel(II) complexes reported in the literature also support the chelate nature of the binuclear species. 相似文献
13.
Pyrolysis of eicosane and redox reactions of the pyrolysis products in supercritical water (SCW) were studied in a batch reactor at 30 MPa, in the temperature range from 450 to 750 °C and with reaction times ranging from 75 to 600 s. The rate constants for eicosane pyrolysis (k" = 1016.5±0.5exp[–(32000±2000)/T] s–1) and for the formation of H2 (k = 1025±0.8exp[–(64000±4000)/T] s–1) were determined. The time and temperature dependences of the heat of reaction were elucidated. Water accelerates pyrolysis and participates in the subsequent transformations of the pyrolysis products. The yield of H2 sharply increases for T > 700 °C. 相似文献
14.
Summary In acid perchlorate media, the title complex undergoes intramolecular redox decomposition generating ultimately Ag+ ion and oxidation products of the ligand. The reaction follows a simple first-order process, and the observed pseudo-first-order rate constant is given by kobs=k0+kKa/[H+] where Ka is the deprotonation constant of the parent complex; pKa is approximately 5.9 at 30°. The values of 105 k0(s–1) and 107 kKa (Ms–1) at 30°, I=1.0 M, are 9.3±0.1 and 11.8±1.3; corresponding H (kJ/mol), S (JK–1 M–1) values are 105±0.5, 23±1 and 79±8,-96±5, respectively. The results are compared with those for similar reaction of (ethylenebisbiguanide)silver(III) and effect of change in ligand structure on kinetic behaviours of these complexes is discussed. 相似文献
15.
Rabindra N. Roy Lakshmi N. Roy Bennett J. Tabor Curtis A. Himes Sarah J. Richards Ashley N. Simon Andrew C. Moore Lydia A. Seing Heather D. Craig Kyle T. Robinson 《Journal of solution chemistry》2004,33(10):1199-1211
The values of the second dissociation constant, pK2, and related thermodynamic quantities of 4-(N-morpholino)butanesulfonic acid (MOBS) and N-tris(hydroxymethyl)-4-aminobutanesulfonic acid (TABS) have already been reported over the temperature range 5–55°C including 37{°}C. This paper reports the pH values of twelve equimolal buffer solutions at designated pH (s) with the following compositions: (a) mixtures of MOBS (0.05 mol-kg–1) + NaMOBS (0.05 mol-kg–1); (b) MOBS (0.08 mol-kg–1) + NaMOBS (0.08 mol-kg–1); (c) MOBS (0.08 mol-kg–1) + NaMOBS (0.08 mol-kg–1) + NaCl (0.08 mol-kg–1); (d) TABS (0.05 mol-kg–1) + NaTABS (0.05 mol-kg–1); and (e) TABS (0.08 mol-kg–1) + NaTABS (0.08 mol-kg–1); and (f) TABS (0.08 mol-kg–1) + NaTABS (0.08 mol-kg–1) + NaCl (0.08 mol-kg–1). Two buffer solutions have ionic strengths I= 0.05 mol-kg–1, another two have I=0.08 mol-kg–1, and the remaining two buffer solutions have I= 0.16 mol-kg–1, which is close to that of the clinical fluids (blood serum). These buffers have been recommended as a useful pH standard for the measurements of physiological solutions. Conventional pH values of all six buffer solutions from 5–55°C, as well as those obtained from the liquid junction potential correction at 25 and 37{°}C have been calculated. The flowing-junction calomel cell has been utilized to measure Ej, the liquid junction potential. 相似文献
16.
Summary The kinetics and mechanisms of the oxidation of Nb(CN)
inf8
sup5–
by the oxyanions S2O
inf8
sup2–
, BrO
inf3
sup–
, and IO
inf4
sup–
have been investigated in alkaline aqueous media (pH 12). The second-order rate constant for the electron transfer reaction between Nb(CN)
inf8
sup5–
and S2O
inf8
sup2–
at 25.0 °C, I = 0.36m (K+), is 11.1± 0.3 m
–1
s
–1 with H
= 30 ± 2kJmol–1 and S
= - 125 + 7JK–1 mol–1. The rate constant for the oxidation of Nb(CN)
inf8
sup5–
by BrO
inf3
sup–
at 25.0 °C, I = 0.20m (Na+), is 2.39 ± 0.08m
–1
s
–1 with H = 28 ± 2kJmol–1 and S
= -139 ± 7JK–1mol–1. The oxidation of Nb(CN)
inf8
sup5–
by IO
inf4
sup–
proceeds by two parallel pathways involving the monomeric IO
inf4
sup–
ion and the hydrated dimer H2I2O
inf10
sup4–
. The second-order rate constant for the oxidation of Nb(CN)
inf8
sup5–
by monomeric IO
inf4
sup–
at 5.0 °C, I = 0.050m (Na+), is (3.3 ± 0.6) × 103
m
–1
s
–1 with H
= 75 ± 6 kJ mol–1 and S
= 94 ± 15 J K–1 mol–1, while the rate constant for the oxidation by H2I2O
inf10
sup4–
is (1.8 ± 0.1) × 103
m
–1
s
–1 with H
= 97 ± 5 kJ mol–1 and S
= 166 ± 16 J K–1 mol–1 under the same reaction conditions. The rate constants for each of the oxidants employed display specific cation catalysis with the order of increasing rate constants: Li+ < Na+ < NH
inf4
sup+
< K+ < Rb+ < Cs+, in the same direction as the electronic polarizability of the cations. The results are discussed in terms of the outer-sphere electron-transfer processes and compared with the corresponding data and mechanisms reported for other metal-cyano reductants. 相似文献
17.
G. Duplâtre A. Haessler A. Marques Netto 《Journal of Radioanalytical and Nuclear Chemistry》1984,82(2):219-228
Ion association has been studied by positron lifetime spectroscopy in aqueous solutions containing the Ni2+ and SO
4
2–
ions at 294 K with the double aim of assessing the reliability of the method for quantitative determination of complex formation constants and of probing the validity of various expressions to calculate single-ion activity coefficients at high ionic strength. The existence of two complexes, identified as NiSO4 and Ni2SO
4
2+
, is shown by the data analysis. Considering the formation constant of the former, KI=(196±10)M–1, determined in previous works leads to discarding several of the expressions commonly used for activity corrections. Two possible values are retained for KI, (193±20)M–1 and (179±20)M–1, while KII related to Ni2SO
4
2+
is better defined, as (2.57±0.14)M–1. 相似文献
18.
Thermochemistry of the solid complex Gd(Et<Subscript>2</Subscript>dtc)<Subscript>3</Subscript>(phen)
Summary A ternary solid complex Gd(Et2dtc)3(phen) has been obtained from reactions of sodium diethyldithiocarbamate (NaEt2dtc), 1,10-phenanthroline (phen) and hydrated gadolinium chloride in absolute ethanol. The title complex was described by chemical and elemental analyses, TG-DTG and IR spectrum. The enthalpy change of liquid-phase reaction of formation of the complex, ΔrHΘm(l), was determined as (-11.628±0.0204) kJ mol-1 at 298.15 K by a RD-496 III heat conduction microcalorimeter. The enthalpy change of the solid-phase reaction of formation of the complex, ΔrHΘm(s), was calculated as (145.306±0.519) kJ mol-1 on the basis of a designed thermochemical cycle. The thermodynamics of reaction of formation of the complex was investigated by changing the temperature of liquid-phase reaction. Fundamental parameters, the apparent reaction rate constant (k), the apparent activation energy (E), the pre-exponential constant (A), the reaction order (n), the activation enthalpy (ΔrHΘ≠), the activation entropy (ΔrSΘ≠), the activation free energy (ΔrGΘ≠) and the enthalpy (ΔrHΘ≠), were obtained by combination of the thermodynamic and kinetic equations for the reaction with the data of thermokinetic experiments. The constant-volume combustion energy of the complex, ΔcU, was determined as (-18673.71±8.15) kJ mol-1 by a RBC-II rotating-bomb calorimeter at 298.15 K. Its standard enthalpy of combustion, ΔcHΘm, and standard enthalpy of formation, ΔfHΘm, were calculated to be (-18692.92±8.15) kJ mol-1 and (-51.28±9.17) kJ mol-1, respectively. 相似文献
19.
Chen S.-P. Gao S.-L. Yang X.-W. Shi Q.-Z. 《Russian Journal of Coordination Chemistry》2004,30(8):566-572
The solubility property of Zn(NO3)2–Thr–H2O system (Thr—threonine) at 25°C in the entire concentration range has been investigated by the phase equilibrium semimicromethod. The corresponding phase diagram and refractive index diagram were constructed. From the phase equilibrium results, the incongruently soluble compounds of Zn(Thr)(NO3)2 · 2H2O, Zn(Thr)2(NO3)2 · H2O, and Zn(Thr)3(NO3)2 · H2O were synthesized and characterized by IR, XRD, TG–DTG, chemical and elemental analyses. The constant-volume combustion energies of the compounds,
c
E, determined by precision rotating bomb calorimeter at 298.15 K, were –6266.88 ± 3.72, –9263.28 ± 2.23, and –11 423.11 ± 6.81 J/g, respectively. The standard enthalpies of combustion for these compounds,
c
H
m
° (complex, s., 298.15 K), were calculated as –2147.40 ± 1.28, –4120.83 ± 0.99, and –6444.68 ± 3.85 kJ/mol and the standard enthalpies of formation,
f
H
m
° (complex, s., 298.15 K), are –1632.82 ± 1.43, –1885.55 ± 1.50, and –2770.25 ± 4.21 kJ/mol. The enthalpies of dissolution of the complexes in a medium of simulated human gastric juice (37°C, pH 1, in the solution of hydrochloric acid),
dis
H
m
° (complex, s., 310 K), which were also measured by a microcalorimeter to be 13.36 ± 0.06, 15.53 ± 0.06, and 17.04 ± 0.05 kJ/mol, respectively. 相似文献
20.
Summary The kinetics and mechanism of exchange of HPDTA in [Fe2HPDTA(OH)2] with cyanide ion (HPDTA=2-hydroxytrimethylenediaminetetraacetic acid) was investigated spectrophotometrically by monitoring the peak at 395 nm (
max of [Fe(CN)5OH]3– at pH=11.0±0.02,I=0.25m (NaClO4) at ±0.1°C).Three distinct observable stages were identified; the first is the formation of [Fe(CN)5OH]3–, the second the formation of [Fe(CN)6]3– from it and the third the reduction of [Fe(CN)6]3– to [Fe(CN)6]4– by HPDTA4– released in the first stage.The first stage follows first-order kinetics in [Fe2HPDTA(OH)2] and second-order in [CN–] over a wide range of [CN–], but becomes zero order at [CN–]<5×10–2
m. We suggest a cyanide-independent dissociation of [Fe2HPDTA)(OH)2] into [FeHPDTA(OH)] and [Fe(OH)]2+ at low cyanide concentrations and a cyanide-assisted rapid dissociation of [Fe2HPDTA(OH)2] to [FeHPDTA(OH)(CN)]3– and [Fe(OH)]2+ at higher cyanide concentrations. The excess of cyanide reacts further with [FeHPDTA(OH)(CN)]3– finally to form [Fe(CN)5OH]3–.The reverse reaction between [Fe(CN)5OH]3– and HPDTA4– is first-order in [Fe(CN)5OH]3– and HPDTA4–, and exhibits inverse first-order dependence on cyanide concentration.A six-step mechanism is proposed for the first stage of reaction, with the fifth step as rate determining. 相似文献