Definition oxidic

Depending on the context, oxidation can either refer to (a) a reaction in which oxygen combines chemically with another substance or (b) any reaction in which electrons are transferred. For the latter definition, oxidation and reduction always occur simultaneously (redox reactions), and the substance that gains electrons is termed the oxidizing agent. Electrons might also be displaced within a molecule without being completely transferred away from it. 

Today, many reactions in aqueous solutions can be described as oxidation-reduction reactions (redox reactions). Oxidation is the process in which the oxidation number of atoms increases. Reduction is the process in which the oxidation number of atoms is decreased or made more negative. In another definition, oxidation is the loss of electrons by an atom, and reduction is the gain of electrons. Let us look at the following reaction ... 

Edmondson et al (1971), who studied the enrichment of whole milk with iron, found that ferrous compounds normally caused a definite oxidized flavor when added before pasteurization. Aeration before addition of the iron reduced the off-flavor. The authors recommended the addition of ferric ammonium citrate followed by pasteurization at 81 °C. Kurtz et al. (1973) reported that iron salts can be added in amounts equivalent to 20 mg iron per liter of skim milk with no adverse flavor effects when iron-fortified dry milk is reconstituted to skim milk or used in the preparation of 2% milk. Hegenauer et al. (1979A) reported that emulsification of milk fat prior to fortification greatly reduced lipid peroxidation by all metal complexes. These researchers (Hegenauer et al. 1979B) concluded that chelated iron and copper should be added after homogenization but before pasteurization by a high-temperature-short-time process. 

The Ni3S2 fragments in the two complexes (263) and (265) have a trigonal bipyramidal geometry with the two S atoms in the apical positions and the three nickel atoms in the equatorial plane, as found in other organometaUic compounds which contain the same Ni unit.1939 The formation of the enneanuclear complex (264), on the contrary, is exceptional and no other complex of this stoichiometry was isolated with analogous tertiary phosphines, with selenium, or with metals other than nickel. It is not possible to assign any definite oxidation number to nickel in complex (264). The lack of two electrons with respect to the situation of nine nickel(II) ions was reported to be essential for the existence of complex (264) because the oxidation is spontaneous and its reduction invariably leads to the decomposition of the cluster compound.19 ... 

The oxidation of a molecule involves the loss of electrons. The reduction of a molecule involves the gain of electrons. Since electrons are not created or destroyed in a chemical reaction, if one molecule is oxidized, another must be reduced (i.e. it is an oxidation-reduction reaction). Thus, by definition, oxidation-reduction reactions involve the transfer of electrons. In the oxidation-reduction reaction ... 

There is no evidence for the significant existence of an Mnlv aquo species in water, nor for the binary hydroxide Mn(OH)4, nor indeed for a definite oxide hydrate the aqueous chemistry of Mn,v is dominated by the insoluble Mn02.211,572... 

There is nothing in the foregoing discussion that restricts it to reactions at the cathode or to ions it holds, in fact, for any electrode process, either anodic, i.e., oxidation, or cathodic, i.e., reduction, using the terms oxidation and reduction in their most general sense, in which the concentration of the reactant is decreased by the electrode process, provided the potential-determining equilibrium is attained rapidly. The fundamental equation (10) is applicable, for example, to cases of reversible oxidation of ions, e.g., ferrous to ferric, ferrocyanide to ferricyanide, iodide to iodine, as well as to their reduction, and also to the oxidation and reduction of non-ionized substances, such as hydroquinone and qui-none, respectively, that give definite oxidation-reduction potentials. 

Definition. — Oxidation sometimes means the withdrawal of hydrogen from a compound, as well as the addition of... 

In favorable cases, in which the metal is plated from a definite oxidation state at 100% current efficiency and in which no secondary oxidation or reduction reactions occur in solution, the determination can be made coulometrically, that is, by application of Faraday s law (Section 5-2). A comprehensive discussion of controlled-potential electrolysis and of coulometric analysis has been given by Lingane. ... 

The lead reductor (E° = —0.126 V) was proposed by Treadwell. If hydrochloric acid more concentrated than 2.5 M is used, lead sulfate films do not form even if highly concentrated sulfuric acid is present. The most important application of the lead reductor is in the reduction of U(VI) to U(IV). Its advantages over the zinc reductor lie mainly in its ability to reduce uranium to a definite oxidation state and in avoidance of certain interferences. 

In the old definition, oxidation is a process in which oxygen is added to an element or compound or, alternatively, one in which hydrogen is removed. The modern definition is that oxidation is a process in which there is electron loss from an element or compound (see Module 2), and it can also be described as the increase in the oxidation state of an element. 

Can oxidation occur without reduction By our definitions, oxidation and reduction are complementary processes oxidahon cannot occur unless reduction also occurs. 

Definitions Oxidation means combination with a more electronegative element or the removal of... 

Oxygen forms the two definite oxides, U02 and UOs, each of which is represented by one or more well defined series of compounds. 

The ratio of H2/H20 was then 75/0.04, for which K = 1875. While the ratio of these equilibrium constants may be taken as an approximate measure of the greater ease of oxidation of a certain range of unsaturated iron atoms, as compared to crystalline iron it must be recognized that the two constants are not strictly comparable in that we do not know what the solid oxide phase is in the latter case. Indeed, since the small number of unsaturated atoms undergoing oxidation is widely distributed among a large number of normal iron atoms, it would not be expected that a definite oxide phase such as Fe204 would be formed. On this basis, the variation in the equilibrium constants is a... 

The most important difference from titanium is that lower oxidation states are of minor importance. There are few authenticated compounds of these elements except in their tetravalent states. Like titanium, they form interstitial borides, carbides, nitrides, etc., but of course these are not to be regarded as having the metals in definite oxidation states. Increased size also makes the oxides more basic and the aqueous chemistry somewhat more extensive, and permits the attainment of coordination numbers 7 and, commonly, 8 in a number of compounds. 

As reference values, Table 3b also presents the amounts of C oxidized after 30 or 120 min for pure tannic acid pp and for the C-pp model. It is evident that, in the absence of an efficient complexing cation, the whole amount of organic C is definitively oxidized within 120 min. Interestingly, in the C-pp model, the large amount of C already oxidized after 30-min could be ascribed to a possible priming catalytic effect by the clay mineral differently, the flakes of pure pp probably clotted, thus needing more time to be completely oxidized [15]. 

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