Reversible reactions, oxygen

Oxidation of Nitric Oxide. Nitric oxide [10102 3-9] reacts slowly with oxygen to yield nitrogen dioxide [10102 4-0] according to the reversible reaction (eq. 12) for which A 7/295 —57kJ/mol of NO consumed (13.6 kcal/mol). 

The reverse reaction (ion formation) can occur in two ways internally, by attack of the penultimate polymer oxygen atom, or externally, by attack of a monomer oxygen atom (chain growth). The external process is about 10 times slower than the internal process in bulk THF (1). Since ion formation is a slow process compared to ion chain growth, chain growth by external attack of monomer on covalent ester makes a negligible contribution to the polymerization process. 

It is not appropriate here to consider the kinetics of the various electrode reactions, which in the case of the oxygenated NaCl solution will depend upon the potentials of the electrodes, the pH of the solution, activity of chloride ions, etc. The significant points to note are that (a) an anode or cathode can support more than one electrode process and b) the sum of the rates of the partial cathodic reactions must equal the sum of the rates of the partial anodic reactions. Since there are four exchange processes (equations 1.39-1.42) there will be eight partial reactions, but if the reverse reactions are regarded as occurring at an insignificant rate then... 

The reversible reaction between hydrogen chloride gas and one mole of oxygen gas produces steam and chlorine gas ... 

Second, reducing bleaches such as lemon juice (in combination with sunlight) or sulfur dioxide convert the double bonds in the chromophore into single bonds, eliminating its ability to absorb visible light. Sometimes the reaction is reversible, where oxygen in the air reacts with the molecule to repair the chromophore, and the stain returns. 

Neither the forward nor the reverse reaction can take place without at least a trace of acid or base, ° ruling out a direct shift of a hydrogen from carbon to oxygen or vice versa. The mechanisms are identical to those in 12-2. ... 

Many chemical changes are reversible reactions. Burning carbon in the form of coal, for instance, is highly exothermic. Oxygen atoms combine with carbon to produce carbon dioxide and heat. But passing carbon dioxide over a bed of hot carbon causes an endo-... 

If the intermediate compound XZ is very unstable, Z cannot serve as a catalyst, while if it is very stable then the reaction stops. The intermediate compound XZ must have the right degree of stability for the catalyst to be effective. It must be borne in mind that the catalyst will accelerate the forward as well as the reverse reactions to the same extent, so that the ratio of the specific rate constants for the forward (kf) the backward (kb) reactions will not be affected. As an example a gaseous reaction between sulfur dioxide and oxygen to yield sulfur trioxide may be considered. The reaction, which can be represented by the equation... 

The second term indicates that by increasing the melt temperature, e.g., by oxygen lancing, to 1850 °C, AG° for the reaction becomes more positive and the reverse reaction leading to retention of chromium in steel becomes favorable. Addition of a deoxidant, e.g., silicon as ferrosilicon, which forms an oxide stabler than Cr203, also leads to further recovery of chromium in steel ... 

The driving force for this transformation is the fact that the less electronegative nitrogen atom is a better Tr-donor than oxygen and can form a stronger bond with the carbene carbon atom. Hence displacement of alkoxide by amines and thiols is commonly observed, but the reverse reactions are seldom seen. 

Alternative paths for decomposition of the metal carboxylate can lead to ketones, acid anhydrides, esters, acid fluorides (1,11,22,68,77,78), and various coupling products (21,77,78), and aspects of these reactions have been reviewed (1,11). Competition from these routes is often substantial when thermal decomposition is carried out in the absence of a solvent (Section III,D), and their formation is attributable to homolytic pathways (11,21,77,78). Other alternative paths are reductive elimination rather than metal-carbon bond formation [Eq. (36)] (Section III,B) and formation of metal-oxygen rather than metal-carbon bonded compounds [e.g., Eqs. (107) (119) and (108) (120). Reactions (36) and (108) are reversible, and C02 activation (116) is involved in the reverse reactions (48,120). 

Continuous Multicomponent Distillation Column 501 Gas Separation by Membrane Permeation 475 Transport of Heavy Metals in Water and Sediment 565 Residence Time Distribution Studies 381 Nitrification in a Fluidised Bed Reactor 547 Conversion of Nitrobenzene to Aniline 329 Non-Ideal Stirred-Tank Reactor 374 Oscillating Tank Reactor Behaviour 290 Oxidation Reaction in an Aerated Tank 250 Classic Streeter-Phelps Oxygen Sag Curves 569 Auto-Refrigerated Reactor 295 Batch Reactor of Luyben 253 Reversible Reaction with Temperature Effects 305 Reversible Reaction with Variable Heat Capacities 299 Reaction with Integrated Extraction of Inhibitory Product 280... 

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