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Energetic Derivation

For the energetic derivation of the barometric formula we consider Fig. 6.9, right sketch. We inspect an exchange of a certain gas from a lower altitude to a higher altitude. This thought experiment is done by removing both portions of gas from the column. [Pg.225]

The gas from the lower altitude is placed up and the gas from the higher altitude is placed down. In the course of the change of position, gravitational work has to be done. This work is obtained from an additional work of compression or expansion that the gas is forced to do, in order that the network is balanced. Therefore, we have for a small volume A V [Pg.225]

Utilizing the ideal gas law, again Eq. (6.46) is obtained. In the previous discussion, we talked about the balance of work, but we did not fix this concept clearly. In thermodynamics, work is associated with energy. So we mean that the gravitational energy is compensated with volume energy. In other words. [Pg.226]

However, there is some shortcoming in this treatment. Since we are dealing explicitly with the temperature of the gas, we have to consider also the energy form that is linked to the temperature, thus more correctly [Pg.226]

To arrive from Eq. (6.50) at Eq. (6.49), we have to take d = 0. However, this is a contradiction to the assumption of an isothermal process. On the other hand, if we consider the energy as a function of the temperature instead of entropy, then the partial derivative with respect to volume is no longer the pressure. [Pg.226]


The sole thermochemical values known to the author for any sulphenic acid, RSOH, are the ionization and ion fragmentation reaction energetics derived values of R = Me, — 45 CH2= CH—, <4 HC=C—, 24 and Ph—, —8kcalmol-1, R. Turecek, L. Brabec, T. Vondrak, V. Hanus, J. Hajicek and Z. Havlas, Collect. Czech. Chem. Commun., 53,2140 (1988). In that we know the heat of formation of no sulphonic acid in the gas phase, we cannot provide an answer to Is it better to view the above ArS02—O—SAr species as an anhydride or an ester That is, our... [Pg.318]

Figure 2.6 illustrates the procedure for the identification of the transitions by means of inflection-point analysis. Plotted are the inverse temperature (F") and its energetic derivative y E). There are two regions, where the weak-sensitivity condition applies to E). One is located around the inflection point at E and the other is the backbending regime surrounding the central inflection point at The latter exhibits the already well-described features of a first-order transition y is positive and the intersection points of the inverse transition temperature /S with the E) curve define the coexistence region. The width is interpreted as the latent heat, which is obviously nonzero > 0. The behavior is qual-... [Pg.64]

Langmuir adsorption isotherm A theoretical equation, derived from the kinetic theory of gases, which relates the amount of gas adsorbed at a plane solid surface to the pressure of gas in equilibrium with the surface. In the derivation it is assumed that the adsorption is restricted to a monolayer at the surface, which is considered to be energetically uniform. It is also assumed that there is no interaction between the adsorbed species. The equation shows that at a gas pressure, p, the fraction, 0, of the surface covered by the adsorbate is given by ... [Pg.234]

As with the quadmpole ion trap, ions with a particular m/z ratio can be selected and stored in tlie FT-ICR cell by the resonant ejection of all other ions. Once isolated, the ions can be stored for variable periods of time (even hours) and allowed to react with neutral reagents that are introduced into the trapping cell. In this maimer, the products of bi-molecular reactions can be monitored and, if done as a fiinction of trapping time, it is possible to derive rate constants for the reactions [47]. Collision-induced dissociation can also be perfomied in the FT-ICR cell by tlie isolation and subsequent excitation of the cyclotron frequency of the ions. The extra translational kinetic energy of the ion packet results in energetic collisions between the ions and background... [Pg.1357]

Polymerizations of methacrylic acid and derivatives are very energetic (MAA, 66.1 kj/mol MMA, 57.5 kJ/mol = 13.7 kcal/mol). The potential for the rapid evolution of heat and generation of pressure presents an explosion hazard if the materials are stored ia closed or poorly vented containers. [Pg.254]

Following the classification of Chapter 4.01, three classes will be considered, (a) Compounds isomeric with aromatic compounds (6), (7) and (8). The quaternary, non-aromatic salts (Scheme 7, Chapter 4.01) will be discussed only in connection with protonation studies which lead to the conclusion of their non-existence. The carbonyl derivatives (9), (10), (13) and (14) will also be included here because it is possible to write an aromatic tautomer for each one, (9 )-(14 ), even if it is energetically unfavoured, (b) Dihydro compounds. In this class not only pyrazolines (15), (16) and (17) but also pyrazolidinones (18) and pyrazolinediones like (1) are included, (c) Tetrahydro compounds. Besides the pyrazolidines (19), the pyrazolidinetriones (2) are included here. [Pg.171]

The conversion of cyclic sulfides to sulfones is accompbshed by more energetic oxidations. Perhalogenated thiolanes [106] and 1,3-dithietanes [107] are oxidized to sulfones and disulfones, respectively, by a mixture of chromium trioxide and nitric acid (equation 98) The same reagent converts 2,4-dichloro-2,4-bis(tnfluoromethyl)-l,3-dif/u cto cs to disulfone derivatives [107], whereas trifluoromethaneperoxysulfonic acid converts the starting compound to a sul-fone-sulfoxide derivative [2(equation 99). [Pg.355]


See other pages where Energetic Derivation is mentioned: [Pg.100]    [Pg.268]    [Pg.148]    [Pg.225]    [Pg.170]    [Pg.132]    [Pg.100]    [Pg.268]    [Pg.148]    [Pg.225]    [Pg.170]    [Pg.132]    [Pg.813]    [Pg.907]    [Pg.1801]    [Pg.1841]    [Pg.2068]    [Pg.2227]    [Pg.2533]    [Pg.3006]    [Pg.556]    [Pg.22]    [Pg.157]    [Pg.164]    [Pg.164]    [Pg.165]    [Pg.32]    [Pg.222]    [Pg.42]    [Pg.369]    [Pg.369]    [Pg.435]    [Pg.306]    [Pg.34]    [Pg.48]    [Pg.14]    [Pg.159]    [Pg.36]    [Pg.178]    [Pg.45]    [Pg.364]    [Pg.525]    [Pg.317]    [Pg.512]    [Pg.66]    [Pg.30]    [Pg.187]    [Pg.198]   


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