Closing Comments

Both the steady-state approximation and the rate-limiting step approximation require the use of the order = moleculaiity property of elementary reactions. For either of these tools to be useful, each reaction in the mechanism must be elementary and the reaction mechanism must be correct. Use of the screening criteria discussed in Section 5.1.3 oftbis chapter can avoid wasting time and energy deriving a rate equation for a proposed mechanism that contains nonelementary reactions. It is important to apply these screening criteria to each reaction in the presumed mechanism, before derivation of the rate equation is begun. 

Even when the screening criteria are rigorously applied, the derived rate equation must be tested against experimental data. After all, we can never be certain that the assumed mechanism is correct, and we can never be certain that each reaction in the mechanism is elementary as written. Moreover, if the RLS approximation is used, we may or may not have identified the RLS correctly, if indeed a single RLS does exist 

Testing of rate equations against data is the subject of the next chapter. 

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Audience and conciseness Are you writing for an expert audience, leaving out unnecessary details Try to find at least three sentences that can be written more clearly and concisely. Have you directed your closing comments (e.g., applications and/or implications) to a more scientific audience Check that you used we and hedging words appropriately. 

Closing Comments. Most kinds of conveyors and elevators are obtainable from several manufacturers, each of whom builds equipment to individual standards of sturdiness, materials of construction, mechanical details, performance, and price. These differences may be decisive in individual cases. Accordingly, a selection usually must be made from a manufacturer s catalog, and ultimately with the advice of the manufacturer. 

Affect-Oriented Programs Alternative Behaviors and Resistance-Skills Training Worksite Programs Programs for College Students Closing Comments on Prevention Summary... 

Hedges JI, Keil RG (1995b) Sedimentary organic-matter preservation—An assessment and speeulative synthesis—closing comment. Mar Chem 49 137-139... 

In Chapter 3, the solution and surface properties of a relatively new class of material, namely, polymeric surfactants, are illustrated in some detail using Flory-Huggins theory and current polymer-adsorption theory. This is followed by a discussion of the phenomenon of steric stabilization of suspended particles and how it is affected by the detailed structure of the stabilizing polymeric species. It concludes with a discussion of the stabilization of emulsions by interfacial and bulk theological effects, and presents closing comments on multiple emulsions. 

A mechanism which does not defy the diffusion limit was proposed and compared to "a double-barrelled shotgun where we reload both barrels at once". The astounding potential of this system was reinforced by his very latest results which reveal that he can now place an ester, thiocyanate and fluoride group with the same precision but as yet lower catalytic turnovers. Attempts to build some more complexity into the system are obviously under way since he mentioned that he is trying to incorporate a cyclodextrin. The reason behind this might be found in his closing comment- "I hesitate to call this an artificial enzyme because it s such a simple system". 

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