Free energy-reaction progress diagram

The balance between the kinetic and thermodynamic factors is illustrated by the free energy-reaction progress diagram (Figure 11) for a transition from... 

Free energy versus reaction progress diagram for the reaction of HBr with H20. 

The free energy versus reaction progress diagram shown in Figure 8.1 is typical for a concerted reaction. There is only one energy maximum there is one transition state, between reactants and products and there is no minimum between them. 

What does the transition state for the SN2 reaction look like Because it is a maximum on the free energy versus reaction progress diagram and any change, either forward to products or backward to reactants, is downhill in energy, the transition state has no appreciable lifetime. Because of this, it cannot be observed directly and any information... 

Free energy versus reaction progress diagrams for the Sn2 reactions of 0 methyl chloride,... 

Free energy versus REACTION PROGRESS DIAGRAM FOR THE SN I REACTION OF TERT-BUTYL CHLORIDE (2-CHLORO-2-METHYLPROPANE) AND ACETATE ANION. 

Draw a free energy versus reaction progress diagram for a reaction that occurs in two steps with a relatively stable intermediate and in which the transition state for the second step is the highest-energy transition state. 

Consider the free energy versus reaction progress diagram for the SN2 reaction shown in Figure 8.1. Does the transition state for this reaction have the C—Cl bond less than half broken, approximately half broken, or more than half broken ... 

The origin of enantioselectivity is thus the lower AG for the path 7" to 8" than for 7 to 8. Figure 12-2 shows a free-energy versus reaction progress diagram for the rate-determining step. 

Figure 12-2 Free-Energy versus Reaction Progress Diagram for the...

An energy diagram is a conceptual tool, so there is some variability in how its axes are labeled. The y-axis of the diagram is usually labeled energy (E), but it is sometimes labeled "enthalpy (/-/)" or (rarely) "free energy (G)." There is an even greater variability in how the x-axis is labeled. The terms "reaction pathway," "reaction coordinate," "course of reaction," or "reaction progress" may be used on the x-axis, or the x-axis may remain without a label. 

The amount of product formed or reactant consumed per unit of time. (p. 145) (potential-energy diagram) A plot of potential-energy changes as the reactants are converted to products. The vertical axis is potential energy (usually free energy, but occasionally enthalpy). The horizontal axis is the reaction coordinate, a measure of the progress of the reaction, (p. 148)... 

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