The Macroscopic Description of Chemical Reaction Rates

In this chapter we discuss the rates of chemical reactions. We restrict our treatment to fluid systems and we will not attempt to treat systems in which the temperature and composition are not constant. Consider a hypothetical chemical reaction  

We can write a chemical equation in the form used in Chapters 3 and 8, 

This equation satisfies the inner urge of physical chemists to write one equation that holds for all cases. 

On the molecular level, a chemical reaction can occur in both directions at the same time. While some reactant molecules are forming products at a rate called the forward rate, other product molecules are forming reactants at a rate called the reverse rate. The observable rate of a chemical reaction is a net rate  

The rate of a reaction can depend on temperature, pressure, and the concentrations or partial pressures of the substances in the system. In many reactions at constant temperature the forward rate depends only on the concentrations of the reactants. If A and B are the reactants. 

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Section 11.1 The Macroscopic Description of Chemical Reaction Rates... 

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