The Development of a Chemical Equilibrium

We have identified three factors that influence the rate of a chemical reaction. In relating these factors to equilibrium considerations, we will examine only concentration and temperature. These variables affect forward and reverse reaction rates differently. A catalyst, on the other hand, has the same effect on both forward and reverse rates. Therefore, a catalyst does not alter chemical equilibrium. A catalyst does cause a system to reach equilibrium more quickly. 

7 Trace and explain the changes in concentrations of reactants and products 

The role of concentration in chemical equilibrium may be illustrated by tracing the development of an equilibrium. The forward reaction in A2 + B2 2 AB is assumed to take place by the simple collision of A2 and B2 molecules, which separate as two AB molecules. The reverse reaction is exactly the reverse process Two AB molecules collide and separate as one A2 molecule and one B2 molecule. 

As soon as the reaction begins, A2 and B2 are consumed, thereby reducing their concentrations in the reaction vessel. As these reactant concentrations decrease, the forward reaction rate declines. Consequently, at Time 1, the forward reaction rate drops to Fj. During the same interval, some AB molecules are produced by the forward 

Go to http //now.brookscole.com/ cracolice3e and dick Chemistry Interactive for the module Concentration Dependence of Reaction Rate. 

---

The Collision Theory of Chemical Reactions Energy Changes During a Molecular Collision Conditions That Affect the Rate of a Chemical Reaction The Development of a Chemical Equilibrium Le Chatelier s Principle The Equilibrium Constant The Significance of the Value of K... 

The Development of a Chemical Equilibrium COAL 7 Trace and explain the changes in concentrations of reactants and products that lead to a chemical equilibrium. 

---