Potassium Tris Oxalato Ferrate Research Articles

Investigations of the Redox Reactions of Potassium Trisoxalatoferrate(III) with Perchlorate Ion in Acidic Medium: A Kinetic Approach

Investigations of the Redox Reactions of Potassium Trisoxalatoferrate(III) with Perchlorate Ion in Acidic Medium: A Kinetic Approach

KINETICS AND MECHANISM OF THE OXIDATION OF TANNIC ACID BY POTASSIUM TRISOXALATOFERRATE (III) IN AQUEOUS HYDROCHLORIC ACID MEDIUM

The kinetics of the redox reaction between tannic acid (TA) and potassium trisoxalatoferrate (III) trihydrate, (K3[Fe(C2O4)3].3H2O) has been studied in aqueous hydrochloric acid medium. The stoichiometry of the reaction determined by the mole ratio method was observed to be 1:1. The kinetic results showed first order dependence with respect to complex and tannic acid concentrations. The experimental data for the reaction system are consistent with the following rate law:where a = 2.0 × 10-3 mol-1 dm3 s-1 and b = 2.1 × 10-3 mol-2 dm6 s-1 at 420 nm and 27.0 ± 1.0 ºC. The rate of reaction was found to increase with increase in [H+] in the acid range used, but decreased with increase in ionic strength of the reaction medium. While the rate of reaction was observed to decrease with increasing dielectric constant of the reaction medium, the addition of CH3COO-, HCOO-, Ni2+and K+ catalyzed the rate of the reaction. The Michaelis-Menten plot of 1/kobs versus 1/[oxidant] gave a straight line with an insignificant positive intercept. The addition of acrylamide to the partially oxidized reaction mixture did gave a gel in the presence of excess methanol. Based on the experimental data, a plausible mechanism involving outer sphere electron transfer has been proposed for the redox reaction between tannic acid and potassium trisoxalatoferrate (III) trihydrate.

KINETICS AND MECHANISM OF THE OXIDATION OF L-ASCORBIC ACID BY POTASSIUM TRISOXALATOFERRATE (III) TRIHYDRATE IN AQUEOUS HYDROCHLORIC ACID MEDIUM

The kinetics of the oxidation of K3[Fe(C2O4)3].3H2O by L-ascorbic acid has been studied in aqueous acidic medium. The stoichiometric studies showed that 1 mole of H2A was oxidized for every 2 moles of Fe(C2O4)33- reduced. Under pseudo-first order conditions of H2A >> Fe(C2O4)33-, the reaction was found to have first order dependence on each of the reactants, giving second order overall. The reaction rate was found to be directly dependent on acid concentration and increased with increase in ionic strength of reaction system. It was also evident that increase in dielectric constant of the reaction medium (D) enhanced the reaction rate and addition of CH3COO-, HCOO-, Mg2+and Li+ catalyzed the rate of the reaction. The oxidation of L-ascorbic acid by potassium trisoxalatoferrate (III) trihydrate is rationalized in terms of absence of ion pair complex formation with outer-sphere reaction pathway characteristics.

ChemInform Abstract: WAVELENGTH AND TEMPERATURE DEPENDENCE IN THE PHOTOLYSIS OF THE CHEMICAL ACTINOMETER, POTASSIUM TRISOXALATOFERRATE(III), AT LONGER WAVELENGTHS

Chemischer InformationsdienstVolume 12, Issue 18 Organoelement Compounds ChemInform Abstract: WAVELENGTH AND TEMPERATURE DEPENDENCE IN THE PHOTOLYSIS OF THE CHEMICAL ACTINOMETER, POTASSIUM TRISOXALATOFERRATE(III), AT LONGER WAVELENGTHS C. H. LANGFORD, C. H. LANGFORDSearch for more papers by this authorC. A. HOLUBOV, C. A. HOLUBOVSearch for more papers by this author C. H. LANGFORD, C. H. LANGFORDSearch for more papers by this authorC. A. HOLUBOV, C. A. HOLUBOVSearch for more papers by this author First published: May 5, 1981 https://doi.org/10.1002/chin.198118312AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume12, Issue18May 5, 1981 RelatedInformation

Wavelength and temperature dependence in the photolysis of the chemical actinometer, potassium trisoxalatoferrate(III), at longer wavelengths

Wavelength and temperature dependence in the photolysis of the chemical actinometer, potassium trisoxalatoferrate(III), at longer wavelengths

Photopolymerization of acrylamide in aqueous solution by potassium trisoxalatoferrate (III)

Photopolymerization of acrylamide in aqueous solution by potassium trisoxalatoferrate (III)

The photochemistry of potassium trisoxalatoferrate(III) trihydrate in the solid state

The gaseous and solid state products of decomposition on uv exposure of polycrystalline K 3[Fe(C 2O 4) 3]·3H 2O have been investigated by mass-spectrometry, ir- and Mössbauer spectroscopy, and chemical and X-ray phase analysis. CO 2 and CO are obtained as photoproducts. The volume ratio, CO:CO 2, generated depends on the exposure conditions and approximately equals 1:3 on photodecomposition in air and 1:2 on decomposition in vacuum. Comparison of the experimental and literature data leads to the following conclusions. The Fe(II)-containing final products of photolysis, radiolysis, and low-temperature (250–260°) thermal decomposition are identical; FeC 2O 4 is missing among the principal final solid state products. Arguments are presented in favor of the view that the Fe(II)-containing final products of photodecomposition is a polymer of composition (K 2[Fe(C 2O 4) 2]) n . On the basis of the experimental and literature data, the flow sheet and stoichiometry of the photodecomposition has been determined. A comparison is made of the spectral dependences of photoconductivity and of photolysis in air. The type of charge carrier is established. Questions related to the mechanisms of photodecomposition are discussed.

The photochemistry of potassium trisoxalatoferrate (III) trihydrate in the solid state

The photochemistry of potassium trisoxalatoferrate (III) trihydrate in the solid state

Formation of iron-57 divalent cation (57Fe2+) in Mössbauer sources of potassium trisoxalatoferrate(III)

The 57Co(electron capture)57Fe process taking place in 57Co-doped crystals of K3FeIII(C2O4)3,3H2O and K3FeIII(C2O4)3 produces some divalent 57FeII. The reduced species may be Fe(C2O4)22–, which has previously been observed in γ-irradiated potassium trisoxalatoferrate(III).

Mössbauer-effect and infrared-absorption study of the radiolysis products of potassium trisoxalatoferrate(III)

Mössbauer-effect and infrared studies on the radiolysis products of potassium trisoxalatoferrate(III) are reported. The principal radiolysis products are identified as cis and trans isomers of potassium bisoxalatobisaquoferrate(II). Room temperature measurements of the quadrupole splittings are: ϵ cis = (2·58±0·03) mm/sec ϵ trans = (3·90±0·04) mm/sec; and of the chemical shifts with respect to sodium nitroprusside: δ cis = (1·48±0·03) mm/sec. δ trans = (1·42±0·03) mm/sec. Evidence is also seen for as many as three additional compounds, either in irradiated samples of potassium trisoxalatoferrate(III) or in synthesized KFe(II)-C 2O 4 complexes. One of these is identified as potassium bisoxalatobisaquoferrate(III) with ϵ = (0·69±0·03) mm/sec and δ = (0·66±0·03) mm/sec. Possible assignments for the others are discussed.

Quantum yields of production of iron(II) and of cobalt(II) in the photolysis of solid potassium trisoxalatoferrate(III) trihydrate and potassium trisoxalatocobaltate(III) trihydrate

Quantum yields of production of iron(II) and of cobalt(II) in the photolysis of solid potassium trisoxalatoferrate(III) trihydrate and potassium trisoxalatocobaltate(III) trihydrate

Mössbauer studies of the decomposition of potassium trisoxalatoferrate(III). Part II

The final product of the radiolysis of potassium trisoxalatoferrate(III) has been identified by analysis, Mössbauer and i.r. spectroscopy as the potassium salt of the dinuclear anion [ox2FeO2C2O2Fe ox2]6– which contains a quadridentate bridging oxalate group O2C2O2. This compound can also be prepared by the thermal decomposition of the salt. The role of such intermediaries as Fe ox2(H2O)22– and other oxalatoferrates is established and a mechanism for the radiolysis discussed. The G value for the decomposition, 7·1 is exceptionally large for the radiolysis of an inorganic solid.