Excess functions graphical determination

The surface excess T represents the total amount of the relevant species in a cylinder of unit cross section, extending from the interface into the bulk of the solution, less the amount that would have been in the same volume, had there been no interface. Fortunately, we do not have to determine how far exactly the interphase extends. The function (C - C ) is integrated to "infinity" - far enough into the bulk that its value has become negligible. It should be noted that on the scale of interest for interphases, "infinity" is not very far. In fact, it is less than 1 xm For the example just discussed, ( )(1 pm) = ( ) exp(—100). The definition of the surface excess is shown graphically in Fig. IH. 

This equation is graphically displayed in Figure 20.9. The progress curves given therein are very useful because they give the enantiomeric excess directly as a function of conversion for fixed Michaelis-Menten parameters of the two reactions (as determined by E. ... 

A reaction between a solid organic compound A and a dissolved reactant B is carried out batchwise in a stirred flask. The massive A-particles dissolve gradually. For a 20% excess of B the total dissolution time appears to be 20 minutes. It is not known where the reaction takes place, at the particle surface or in the bulk of the liquid. How do we determine which mechanism prevails We measure the conversion of A as a function of time, and determine the dissolution time We make two graphic plots ... 

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