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Generalized rate laws

The transfer reactions follow second-order kinetics, the general rate law being... [Pg.389]

If the decomposition reaction follows the general rate law, the activation energy, heat of decomposition, rate constant and half-life for any given temperature can be obtained on a few milligrams using the ASTM method. Hazard indicators include heats of decomposition in excess of 0.3 kcal/g, short half-lives, low activation energies and low exotherm onset temperatures, especially if heat of decomposition is considerable. [Pg.246]

We can identify this combination of constant quantities as a new constant, k [ 3] — Here, obs is an abbreviation for observed. Using, we can simplify the rate law to rate = j4"()bs [isoprene]. It is important to remember that is an observed, experimental nte constant, but it is not the true rate constant ( ) that appears in the general rate law. [Pg.1076]

Isolating isoprene as the only reactant whose concentration changes simplifies the general rate law to a form that can be tested against the single concentration rate laws ... [Pg.1076]

A stopped-flow study of the Ce(IV) sulphate oxidations of several of these substances to the corresponding disulphide produced a general rate law... [Pg.394]

Now that we have a definition of rate, we need to develop a basic model to describe the rates of chemical reactions. The basic model takes the form of a rate law. A general rate law allows us to relate the rate of a reaction to the concentration of the reactants present. It makes sense, intuitively, that at low reactant concentrations the rate of the reaction will be quite slow. Also, at high reactant concentrations in the same reaction we would expect a faster rate. The general rate law reflects this intuition by stating that, in simple reactions, such as the one in Eq 4.1, we define the rate according to Eq. 4.4. [Pg.82]

Friedel-Crafts acylation, in cases where the kinetics can readily be monitored, is often found to follow the same general rate law as... [Pg.143]

The reaction is usually found to follow the general rate law ... [Pg.148]

If the concentrations of only the electron donor and acceptor are considered to vary, each mD+ is invariant and the term ] [ n/ 1 in Equation 18.23 reverts to a half-saturation constant K[y Similarly, the corresponding term in Equation 18.24 may be represented by K A. Now, we see the dual Monod equation (Eqn. 18.16) is a specific simplification of the general rate law (Eqn. 18.22). [Pg.264]

Tobe,9 in aqueous solution the general rate law for complex formation (eliminating charge for simplicity),... [Pg.10]

Although Eq. (4.32) can be derived as a general rate law expression under the assumption of an exponential decrease in number of available sorption sites with r and/or a linear increase in activation energy of sorption with T, the Elovich Equation is perhaps best regarded as an empirical one for the characterization of rate data (Sposito, 1984). [Pg.105]

The scheme of Fig. 5.5a corresponds to steady state conditions (Table 5.1). We can now apply the general rate law (Eqs. 5.7, 5.8), the rate of the ligand-promoted dissolution, Rl, is proportional to the concentration of surface sites occupied by L (metal-ligand complex, >ML) or to the surface concentration of ligands, C (mol nr2) ... [Pg.166]

Chemical adsorption or surface complexation as given in Eq. (6.21) attempts to relate to the "collision" factor A in Eq. (6.12) to the surface concentrations of adsorbed ions. By analogy to the treatment of activated processes the following "general" rate law for the rate of nucleation of the mineral (AB) on a foreign surface could then be proposed... [Pg.225]

The general rate law equation for this reaction is given helow. [Pg.281]

You need to find the value of m, n, and k in the general rate law equa-... [Pg.282]

What are the exponents m and n, and the rate constant, in the following general rate law equation ... [Pg.306]

Several trials of the reaction are carried out, each using a piece of magnesium ribbon of a fixed length. This is analogous to constant concentration. The general rate law equation can now be written as follows ... [Pg.318]

To verify the homogeneous nature of Rh-3-SILP catalysts, as previously suggested based on IR and NMR spectroscopic studies, [30] kinetic experiments have also been conducted with the catalyst. Here, a continuous fixed-bed reactor setup equipped with online gas-chromatography, described elsewhere in detail, [31] was applied. The general rate law for the hydroformylation of propene was assumed ... [Pg.155]

The macrocycles are generally characterized by their extreme resistance to dissociation, (see however Prob. 6). The kinetics of acid-promoted dissociation of an extensive series of Ni(II) and Cu(II) complexes, (ML) have been reported,The general rate law is (see Prob. 2, Chap. 2) ... [Pg.227]

Outer-sphere (OS) reaction rates and rate laws can be defined for solvolysis of a given complex. Complex formation is defined as the reverse reaction— that is, replacement of solvent (S) by another ligand (L ). Following the arguments of Tobe, in aqueous solution the general rate law for complex formation (eliminating charge for simplicity). [Pg.11]

The reaction order is equal to the exponent of the concentration in the rate law. A general expression for the rate law can be written using the standard reaction A + B —> products, where A and B represent reactants. The general rate law for this expression can be written as... [Pg.143]

Equations that relate the rate of a reaction to the concentration of some species (which can mean either reactant or product) in solution cire called rate laws. The exact form that a rate law assumes depends on the reaction involved. Countless research studies have described the intricacies of rate in chemical reactions. Here, we focus on rate laws for simpler reactions. In general, rate laws take the following form ... [Pg.196]

The above observations clearly indicate the inadequacy of the simple second-order law for describing the reaction rate outside the conditions of strongly acidic solutions and low initial cerium(III) concentrations. A more general rate law, suggested by considerations of the reaction mechanism (see Discussion), which takes into account the inhibiting effect of cerium(III), is of the form... [Pg.239]


See other pages where Generalized rate laws is mentioned: [Pg.246]    [Pg.290]    [Pg.477]    [Pg.20]    [Pg.87]    [Pg.89]    [Pg.90]    [Pg.9]    [Pg.60]    [Pg.100]    [Pg.162]    [Pg.162]    [Pg.163]    [Pg.164]    [Pg.390]    [Pg.443]    [Pg.168]    [Pg.230]   


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