Reaction interpretation

Since the free energy of a molecule in the liquid phase is not markedly different from that of the same species volatilized, the variation in the intrinsic reactivity associated with the controlling step in a solid—liquid process is not expected to be very different from that of the solid—gas reaction. Interpretation of kinetic data for solid—liquid reactions must, however, always consider the possibility that mass transfer in the homogeneous phase of reactants to or products from, the reaction interface is rate-limiting [108,109], Kinetic aspects of solid—liquid reactions have been discussed by Taplin [110]. 

Use data in Table 7.3 or Appendix 2A to calculate the standard reaction entropy for each of the following reactions at 25°C. For each reaction, interpret the sign and magnitude of the reaction entropy, (a) The formation of... 

A Chemical-Reaction Interpreter for Simulation of Complex Kinetics... 

Figure 2. Geoffroys 1718 affinity table for single displacement reactions interpreted as particle interchanges.

There is always a good possibility that the mechanism of radical-cation formation reactions interpreted as ET process actually proceeds through ionic pathways, while reactions described by an ionic mechanism in fact may involve an ET process. The risk of wrong interpretation may be in part due to the complex reactivity of radical cations, described in an excellent review61. 

The addition of O2 (whether or A ) to 138 or 4 has apparently not been studied theoretically although selection rules for singlet oxygen reactions/ interpretation of substituent effects and orbital correlations for homolytic fission and re-formation of the peroxide bond in 9,10-diphenyl-anthracene peroxide and rubrene peroxide have been published. 

The intermediate appears to be the acid anhydride formed by Glu-270.414 415 The conformation of the intermediate was deduced by ENDOR spectroscopy and its formation and reaction interpreted according to stereoelectronic principles.416... 

A spectrum of metal compound reactivities in petroleum could arise for several reasons. Nickel and vanadium exist in a diversity of chemical environments. These can be categorized into porphyrinic and non-porphyrinic species vanadyl and nonvanadyl or associated with large asphaltenic groups and small, isolated metal-containing molecules. Each can be characterized by unique intrinsic reactivity. Reaction inhibition which occurs between the asphaltenes and the nonasphaltenes, as well as between Ni and V species, can also contribute to reactivity distributions. The parallel reaction interpretation of the observed reaction order discrepancy is therefore compatible with the multicomponent nature of petroleum. Data obtained at low conversion could appear as first order and only at higher conversions would higher-order effects become obvious. The... 

Aube and co-workers have found that enolizable ketones react with benzyl azide in triflic acid to yield /V-(phenylamino)-methylated products [Eq. (5.354)]. The transformation is an aza-Mannich reaction interpreted with the involvement of the Mannich reagent A -phenyl iminium ion 295 formed in situ in a Schmidt rearrangement. Cyclic tertiary alcohols react with alkyl azides in triflic acid to yield N-alkylamines (296, 297)983 [Eq. (5.355)]. The Schmidt rearrangement was used to transform Merrifield resin into amino-polystyrene resin by reacting the azido derivative in excess triflic acid (CH2CI2, 0°C).984... 

Suggest structures for the products of these reactions, interpreting the spectroscopic data. You are not expected to write mechanisms for the reactions and you should resist the temptation to work out what should happen from the reactions. These are all unexpected products. 

The active centres of polymerization are produced by the addition of the primary radical to the monomer, i. e. to a n electron system. Only rarely is this simple process, and almost all branches of theoretical chemistry and chemical physics have contributed to its elucidation. The addition is a bimolecular reaction interpreted kinetically as a second-order reaction [125]. Unfortunately, most studies have been concerned with reaction in the gaseous phase. In the condensed phase, the probability that the excess energy of the reaction product will be removed by collision with a third molecule is very much higher thus the results obtained in the gaseous phase need not be valid generally. 

Due to the mechanistic diversity and/or uncertainty of such reactions, interpretation of these effects is not as straightforward as for peracid epoxidations. 

The thermal reaction occurring in HBr-D2 mixtures and the HBr catalyzed ortho-para hydrogen conversion have been studied by Steiner Thermal conductivity measurements were used to follow the reaction. Interpreting the results in terms of an atomic chain mechanism which allowed for the competition between... 

In fact, in my opinion, the concept of activation should be the starting point for many new investigations. It should lead to new reagents for synthesis as well as new reaction interpretations. 

Since chain reactions are so common, it would be unreasonable to expect all mechanisms to fit neatly into the four examples of Table 1.3. Illustration 1.5 has already given some further information on thermal decomposition reactions following Rice-Herzfeld mechanisms. Before going on to additional reaction systems, we should add a few comments on the two-active-center reaction illustrated by the combination of hydrogen and bromine in the gas phase. This is probably the first reaction for which a suitable chain sequence was identified. The kinetics of the reaction were carefully studied and reported as early as 1907 [M. Bodenstein and S.C. Lind, Z. Physik. Chem., 57, 168 (1907)] and the chain reaction interpretation of the reported kinetics, as shown in the tabulation of Table 1.3, was given over a decade later [J.A. Christiansen, Kgl. Danske Videnskab. Selskab., 1, 14 (1919) K.F. Herzfeld, Ann. Physik. Chem., 59, 635 (1919) M. Polanyi, Z. Elektrochem., 26, 50 (1920)]. A through discussion of this is given in the text by Frost and Pearson. 

Whether an adverse drug reaction is of the allergic, the toxic, the idiosyncratic or any other type, may be at first unclear and debatable. The first step is observation, recognition and study of the reaction. Interpretation may take years of research or, it may not be possible at all with the methods currently available. 

As indicated earlier, a chemical equation is a shorthand description of a chemical reaction. Interpretation of a balanced equation gives us the following information ... 

When adsorption is significant in an electro-organic reaction, interpretations of reaction order in terms of mechanisms must be made with care. Consider a case where the current density at a given constant potential E is... 

Detection of IgE antibodies to PVP has been reported in a subject who experienced an immediate reaction that included urticaria and angio-edema following topical application of povidone-iodine, but the weak reaction, interpreted as a positive result after simple adsorption of PVP to a microtiter plate, is not entirely convincing. 

Thiel V, Wannowius K-J, Wolff C, Thiele CM, Plenio H. Ring-Closing Metathesis Reactions Interpretation of Conversion—Time Data. Chem Eur J. 2013 19(48) 16403-16414. 

Figure 8.6 Schematic free-energy diagram for slow proton-transfer reactions. Interpretation of the Brpnsted relation.

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