What is defined as a dynamic equilibrium?

A dynamic equilibrium is characterized by the condition where the rates of the forward and reverse reactions are equal. This means that the system is in a state of balance where the amount of reactants and products remains constant over time, even though both reactions continue to occur. In this state, the concentrations of the reactants and products do not change, because they are being produced and consumed at the same rate.

In contrast, other scenarios described in the options do not fit the definition of dynamic equilibrium. For instance, a constant increase in the concentration of products suggests that the reaction is still proceeding and has not yet reached equilibrium. Similarly, if the reaction were to complete with only products present, it indicates that equilibrium has not been established since there would be no reactant left to reverse the reaction. Lastly, having zero concentrations for both reactants and products would signify that the reaction has not occurred or has gone to completion, which also does not represent a dynamic equilibrium. Thus, the correct understanding of dynamic equilibrium hinges on recognizing the equal rates of the forward and reverse reactions.