At equilibrium rate of forward reaction becomes equal to rate of backward reaction.

Answer

To solve the question, let's break down the concept of equilibrium in chemical reactions step by step.

### Step-by-Step Solution:

1. **Understanding Chemical Reactions**:
- In a chemical reaction, reactants are converted into products. For example, consider a reversible reaction:
\[ A + B \rightleftharpoons C + D \]

2. **Forward and Backward Reactions**:
- The forward reaction is when reactants \( A \) and \( B \) are converted into products \( C \) and \( D \).
- The backward reaction is when products \( C \) and \( D \) are converted back into reactants \( A \) and \( B \).

3. **Rate of Reactions**:
- The rate of a reaction is a measure of how quickly reactants are converted to products.
- The rate of the forward reaction can be expressed as \( \text{Rate}_{\text{forward}} = k_f [A][B] \), where \( k_f \) is the rate constant for the forward reaction.
- The rate of the backward reaction can be expressed as \( \text{Rate}_{\text{backward}} = k_b [C][D] \), where \( k_b \) is the rate constant for the backward reaction.

4. **Equilibrium Condition**:
- At equilibrium, the rates of the forward and backward reactions become equal:
\[ \text{Rate}_{\text{forward}} = \text{Rate}_{\text{backward}} \]
- This means that the concentration of reactants and products remains constant over time, even though both reactions are still occurring.

5. **Concentration at Equilibrium**:
- At equilibrium, the concentrations of reactants \( [A] \) and \( [B] \) and products \( [C] \) and \( [D] \) do not change. This is because the rate at which \( A \) and \( B \) are converted into \( C \) and \( D \) is exactly balanced by the rate at which \( C \) and \( D \) are converted back into \( A \) and \( B \).

6. **Conclusion**:
- Therefore, the statement "At equilibrium, the rate of forward reaction becomes equal to the rate of backward reaction" is true because the system has reached a state where the concentrations of reactants and products remain constant, indicating a dynamic balance between the forward and backward processes.