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Manganous ion and

The rate of oxidation is reduced by one half on addition of manganous ions and the following Arrhenius parameters were recorded... [Pg.324]

A rapid exchange takes place between manganous ion and manganic oxalate ion. [Pg.262]

Stamm took advantage of the insolubility of barium. manganate to stabilize the manganate ion and to increase the electrode potential. [Pg.325]

Bromfield, S.M. and David, D.J., 1976. Sorption and oxidation of manganous ions and reduction of manganese oxide by cell suspensions of a manganese oxidising bacterium. Soil Biol. Biochem., 8 37—43. [Pg.287]

The product of the reaction of e"q with the permanganate ion is the manganate ion and with the persulphate ion is the sulphate ion radical, both of which have been identified from pulse radiolysis studies, viz. [Pg.442]

Figure 6 Effect of electron acceptors on the reduction of arsenate (O) to arsenite ( ) in estuarine sediment slurries incubated (a) without additions, (b) with sulfate ions, (c) with phosphate or manganic ions, and (d) with nitrate or ferric ions. (From Ref. 39.)... Figure 6 Effect of electron acceptors on the reduction of arsenate (O) to arsenite ( ) in estuarine sediment slurries incubated (a) without additions, (b) with sulfate ions, (c) with phosphate or manganic ions, and (d) with nitrate or ferric ions. (From Ref. 39.)...
The method can be used in the range of 0.1-2.0 mg/dm bromide concentration. Manganous ions and naturally, bromates interfere with the determination. [Pg.188]

A similar system to that for dicarboxylic acids has been described by Akazawa and Conn (1958) for pyridine nucleotides. Chance (1951) had shown that DPNH was a hydrogen donor for the peroxidatic activity of the enzyme, albeit not a very effective one. Akazawa and Conn found that an oxidatic reaction was also catalyzed by peroxidase if manganous ions and a monohydric phenol were present. In its sensitivity to catalase, copper salts, and cyanide, this system closely resembles the classical peroxidase-catalyzed oxidations. Although these investigators did not analyze their system in the terms put forward by Yamazaki, they found that oxidogenic donors were stimulatory and redogenic donors inhibitory in this reaction. [Pg.300]

The complexes of manganese(III) include [Mn(CN)g] (formed when manganesefll) salts are oxidised in presence of cyanide ions), and [Mnp5(H20)] , formed when a manganese(II) salt is oxidised by a manganate(VII) in presence of hydrofluoric acid ... [Pg.389]

The Mn ion is so unstable that it scarcely exists in aqueous solution. In acidic aqueous solution, manganic compounds readily disproportionate to form Mn ions and hydrated manganese(IV) oxide, Mn02 2H20 in basic solution these compounds hydroly2e to hydrous manganese(III) oxide, MnO(OH). Sulfuric acid concentrations of about 400 450 g/L are required to stabilize the noncomplexed Mn ion in aqueous solutions. [Pg.506]

Iron and Manganese Removal. Soluble ferrous and manganous ions are oxidized by ozone (typicaUy 2.5 ppm) to less soluble higher... [Pg.501]

The manganous ion [16397-91 -4] in solution then reacts with higher valent manganese oxide and zinc ions in solution to form a new phase called... [Pg.521]

Use oxidation numbers to balance the reaction between ferrous ion, Fe+2, and permanganate ion, MnOr, in acid solution to produce ferric ion, Fe+3, and manganous ion, Mn+2. [Pg.223]

However, the ability to act as a builder encompasses much more than so far been mentioned. Builders influence the coagulation of solid soil, often form a buffer system, and promote the soil suspending activity of washing liquors. They are further able to reduce the catalytic effect of ferric and manganic ions. Thus they support the stabilization of peroxides in detergents. Similarly, rancidness caused by catalytic processes of soap and fragrances can be avoided. [Pg.600]

The reaction of the permanganate and manganous ions can take place under conditions where either Mn02(s) or Mn(III), which decomposes slowly, are the main products, viz. [Pg.95]

In acidic solution MnOj is usually the end product, although particularly vigorous reductants, e.g. iodide and oxalate ions, convert permanganate to manganous ions. Mn(III) is stable only in acidic solution or in the form of a complex, e.g. with pyrophosphate ion, and it has seldom been reported as the end product of a permanganate oxidation, e.g. for that of Mn(II) in a phosphate buffer and for those of alcohols and ethers in the presence of fluoride ion. ... [Pg.279]

Westheimer has also reviewed the induced oxidations by the Cr(VI)-As(III) couple of iodide, bromide and manganous ions vide supra). The induction factor of 0.5 for Mn(II) implies an intermediate tetravalent chromium species however, the factor of 2 for iodide points to a pentavalent chromium intermediate. Both... [Pg.288]

Early work of Dhar established that oxidation of oxalic acid by chromic acid occurs readily, but some of his kinetic data are unreliable as the substrate itself acted as the source of hydrogen ions. The reaction is first-order in oxidant and is subject to strong manganous ion catalysis (as opposed to the customary retardation), the catalysed reaction being zero-order in chromic acid. This observation is related to those found in the manganous-ion catalysed oxidations of several organic compounds discussed at the end of this section. [Pg.323]

The permanganate oxidation of oxalic acid has been studied exhaustively and has been reviewed by Ladbury and Cullis . It is characterised by an induction period and a sigmoid dependence of rate upon time. Addition of manganous ions eliminates the induction period and produces first-order decay kinetics . Addition of fluoride ions, however, practically eliminates reaction . ... [Pg.323]

Dhar noted that the oxidation of oxalic acid by chromic acid is markedly accelerated on adding manganous ions, the reaction order in Cr(VI) changing from one to zero. Bobtelsky and Glasner ° found the oxidation of bromide ions by chromic acid in aqueous sulphuric acid to follow kinetics... [Pg.327]

The oxidation of oxalic acid by mercuric chloride to give CO2 and mercurous chloride is a classic example of an induced reaction. This reaction is extremely slow unless small quantities of chromic acid and manganous ions are added, whereon facile reduction takes place Addition of permanganate or persulphate and some reducing agents is also effective and the oxidation proceeds readily under photo- or X-irradiation (Eder s reaction). The large quantum yield points to a chain mechanism , which could also function with an inducing oxidant, viz. [Pg.352]

The kinetics of the initial stages of the oxidation of some a-hydroxy-carboxylic such as lactic, malic and mandelic acids by chromic acid have been studied by Bakore and Narain . The initial reaction resembles the oxidation of a secondary alcohol to ketone. The authors concluded that the rate determining step involves C-H bond rupture at the a-carbon atom. The rate of oxidation of these acids is reduced to one-half by the addition of manganous ions, when the concentration of the latter is commensurable with that of the acids. [Pg.531]

The oxidation of tartaric and glycollic acid by chromic acid also induces the oxidation of manganous ions. In the presence of higher concentrations of manganese(II) the rate of oxidation of the acids is diminished to about one-third of that in the absence of manganous ions. The decrease of the rate has been attributed to manganese(II) catalysis of the disproportionation of the intermediate valence states of chromium probably chromium(IV). [Pg.531]

The proposed mechanism for the functionality of MnP involves the oxidation of manganous ions Mn2+ to Mn3+, which is then chelated with organic acids. The chelated Mn3+ diffuses freely from the active site of the enzyme and can oxidize secondary substrates [25],... [Pg.161]

Assuming standard conditions, what is E for a cell in which iron metal reacts with manganous ion to form ferrous ion and manganese metal ... [Pg.416]


See other pages where Manganous ion and is mentioned: [Pg.20]    [Pg.394]    [Pg.528]    [Pg.529]    [Pg.153]    [Pg.154]    [Pg.317]    [Pg.316]    [Pg.20]    [Pg.394]    [Pg.528]    [Pg.529]    [Pg.153]    [Pg.154]    [Pg.317]    [Pg.316]    [Pg.103]    [Pg.317]    [Pg.23]    [Pg.515]    [Pg.520]    [Pg.104]    [Pg.107]    [Pg.691]    [Pg.93]    [Pg.311]    [Pg.320]    [Pg.583]   


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Ferric and manganous ions

Manganate ion

Manganates

Mangane

Manganes

Manganic ions

Manganism

Manganous

Manganous ion

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