Misconceptions in General

One classical misconception in general chemical kinetics, but particularly worrisome in catalysis, is the following ... 

Electrostatics in Non-Aqueous Media. A popular misconception in studies of non-aqueous dispersions concerns electrostatic effects. Because these are more difficult to measure than in aqueous media, there has been a general tendency to ignore them completely. However, the few investigators who have measured zeta-potentials or electrodeposition with these systems have become convinced of their importance. With the advent of modern commercial instrumentation for zeta-potentials in non-aqueous media it is to hoped that these effects will be measured rather than ignored. 

While most derivations focus on the equation of motion, an equally important aspect of the MFT method is the correct representation of the quantum-mechanical initial state. It is well known that the classical limit of quantum dynamics in general is represented by an ensemble of classical orbits [23, 24, 26, 204]. Hence it is not appropriate to use a single classical trajectory, but it is necessary to average over many trajectories, the initial conditions of which are chosen to mimic the quantum nature of the initial state of the classically treated subsystem. Interestingly, it turns out that several misconceptions concerning the theory and performance of the MFT method are rooted in the assumption of a single classical trajectory. 

Sanger and Grenbowe (75) combined the data from their earlier study with those of Garnett and Treagust, and compiled a list of students common misconceptions in electrochemistry. The list covered galvanic cells, electrolytic cells, and concentration cells. The role attributed to misleading or erroneous statements in textbooks as sources of misconceptions led these authors to analyze a number of general chemistry textbooks (75). 

Several important points must be made in connection with Table 1.16.1 (i) There is a common misconception to the effect that the performance of work is exclusively associated with a change in the internal energy of the system. Clearly, in general this is not the case. If, for example, a process is carried out at constant T and P, then the performance of work other than P-V work is associated with a change of the Gibbs free energy. (ii) For each of the five conditions under which processes are shown to occur in Table 1.16.1, there is a special function of state best suited to describe the process furthermore, under the various indicated conditions the inexact... 

There are numerous misconceptions or generalizations about placebo response. Common misconceptions include but are not limited to the following One-third of all patients respond to placebo therapy response is brief certain demographic or personality factors predict response those who respond to placebo therapy do not have medical problems and giving placebo is equivalent to no intervention. In addition, placebo response in one clinical trial or disease state does not ensure equivalent placebo response in other disease states. 

The reference value bo in Eqs. [3] and [4] is not the equilibrium bond length in any particular molecule (except by chance).This is a common misconception, and indeed the value of bo is sometimes taken from an experimentally observed value. This is not valid. Rather, bo is the bond length of the particular bond in a virtual, unperturbed state, that is, in a hypothetical state where the bond exists as an isolated entity, outside the molecule, and not affected by any external forces. In any real molecule, there are forces from neighboring atoms and interactions with other internals, which stretch or compress the bond from its unperturbed value. The more strained the molecule, in general, the farther the bond in the equilibrium molecular structure will be from the reference value bo. An obvious example of this is the classic example of the C —C bond in the strained molecule tri-r rt-butylmethane, whose equilibrium value is 1.61 A, far from the typical reference value of 1. .32-1.53 used in standard force fields. Usually, for most unstrained molecules, bo is close to the equilibrium values. 

Zoller, U. (1990). Students misunderstandings and misconceptions in college freshman chemistry (General and Organic). Journal of Research in Science Teaching, 27(10), 1053-1065. 

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