Describe the differences between the intermediates and transition states in a reaction mechanism.

Intermediates are stable molecules formed during a reaction, while transition states are unstable and short-lived.

Intermediates are molecules that are formed during a reaction and can be isolated and studied. They are stable and have a longer lifetime than transition states. Intermediates are formed when reactants collide and form a new molecule that is not the final product. This molecule can then react further to form the final product. For example, in the reaction between hydrogen and oxygen to form water, the intermediate is the hydroxyl radical (OH), which is formed when hydrogen and oxygen react.

Transition states are unstable and short-lived molecules that form during a reaction. They are the highest energy point in the reaction and represent the point of maximum energy. They are formed when reactants collide and form a new molecule that is not stable and quickly breaks down to form the final product. Transition states are important because they determine the rate of the reaction. The lower the energy of the transition state, the faster the reaction will be. For example, in the reaction between hydrogen and oxygen to form water, the transition state is the activated complex, which is formed when hydrogen and oxygen collide and form a molecule that is not stable and quickly breaks down to form water.

In summary, intermediates are stable molecules formed during a reaction, while transition states are unstable and short-lived molecules that represent the highest energy point in the reaction. Both intermediates and transition states are important in understanding the mechanism of a reaction.