A conclusion is to be drawn about the mechanism of the reaction in Figure 15-10, which does not show a change over an initial period in the absorbance at 244 nm when the concentration of the base is doubled. Concept introduction: The kinetics of an elimination reaction can be determined by monitoring the absorbance of the product’s λ max as a function of time. The reacting species, substrate, or base, which affects the rate of the reaction can be determined in this way. If the variation in the absorbance shows a difference when the concentration of one of these is changed, then the rate of the reaction depends on the concentration of that species. Essentially, it means that that particular species must be involved in the rate-determining step. If both affect the rate of the reaction, then the mechanism must be E2, if only the substrate concentration affects the rate of the reaction, the mechanism must be E1.

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Chapter 15, Problem 15.8YT

Interpretation Introduction

Interpretation:

A conclusion is to be drawn about the mechanism of the reaction in Figure 15-10, which does not show a change over an initial period in the absorbance at 244 nm when the concentration of the base is doubled.

Concept introduction:

The kinetics of an elimination reaction can be determined by monitoring the absorbance of the product’s λmax as a function of time. The reacting species, substrate, or base, which affects the rate of the reaction can be determined in this way. If the variation in the absorbance shows a difference when the concentration of one of these is changed, then the rate of the reaction depends on the concentration of that species. Essentially, it means that that particular species must be involved in the rate-determining step. If both affect the rate of the reaction, then the mechanism must be E2, if only the substrate concentration affects the rate of the reaction, the mechanism must be E1.

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