Certainly! Let's go through the question step-by-step to determine when the given chemical system reaches dynamic equilibrium.
The reaction provided is:
[tex]\[ 2 \, \text{SO}_2(g) + \text{O}_2(g) \longleftrightarrow 2 \, \text{SO}_3(g) \][/tex]
To understand dynamic equilibrium, it's important to grasp the fundamental concepts of chemical equilibrium.
### Key Points in Chemical Equilibrium:
1. Definition of Dynamic Equilibrium: Dynamic equilibrium in a chemical system is the state where the concentrations of all reactants and products remain constant over time. This happens because the rate at which the reactants are converted to products (forward reaction) is equal to the rate at which the products are converted back to reactants (reverse reaction).
2. Rates of Reactions: In a dynamic equilibrium, the forward and reverse reactions do not stop. Instead, they continue to occur at the same rate, ensuring that the overall concentrations of the reactants and products remain constant.
### Analyzing the Given Options:
1. "When the forward and reverse reactions stop": This is incorrect because, at dynamic equilibrium, the reactions are still occurring. The key feature of dynamic equilibrium is that the forward and reverse reactions continue but at the same rate.
2. "When the rate of the forward reaction is higher than the rate of the reverse reaction": This would imply that the system is still shifting towards more product formation, and equilibrium has not been reached. Therefore, this option is incorrect.
3. "When the concentration of the reactants is higher than the concentration of the products": The equilibrium state depends on the balance of rates rather than the absolute concentrations of reactants and products. Therefore, this option is misleading and incorrect.
4. "When the rates of the forward and reverse reactions are equal": This is the correct definition of dynamic equilibrium. At this point, the reaction rates are balanced, meaning the system has reached a state where the concentrations of reactants and products remain constant over time.
### Conclusion:
The given chemical system reaches dynamic equilibrium when the rates of the forward and reverse reactions are equal.
This is described by the choice:
[tex]\[ \boxed{\text{When the rates of the forward and reverse reactions are equal.}} \][/tex]
