When the rate of the forward reaction equals the rate of the reverse reaction, the net concentrations of all species do not change and the system is at _____.

When the rate of the forward reaction equals the rate of the reverse reaction, the net concentrations of all species do not change, and the system is at chemical equilibrium.

In this state, the dynamic process of the reactions continues, but the overall concentrations of the reactants and products remain constant over time. This balance reflects the principle of reversibility in chemical reactions, where the forward and reverse processes occur at equal rates, resulting in a stable condition. The concept of chemical equilibrium is fundamental in understanding reaction dynamics, Le Chatelier's principle, and the behavior of systems under changes in conditions such as concentration, temperature, and pressure.