When the rate of formation of reactants is equal to the rate of formation of products, this is known as,

Options

A. Chemical reaction
B. Chemical equilibrium
C. Chemical kinetics
D. None

Answer

To solve the question, "When the rate of formation of reactants is equal to the rate of formation of products, this is known as," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Concept**:
- In a chemical reaction, reactants are transformed into products. The rates at which these transformations occur can change over time.

2. **Defining Equilibrium**:
- When a chemical reaction reaches a state where the rate of formation of reactants is equal to the rate of formation of products, the system is said to be in equilibrium. This means that the concentrations of reactants and products remain constant over time.

3. **Identifying the Type of Equilibrium**:
- This specific condition is referred to as **chemical equilibrium**. At this point, the forward reaction (reactants forming products) occurs at the same rate as the reverse reaction (products forming reactants).

4. **Conclusion**:
- Therefore, the answer to the question is that this condition is known as **chemical equilibrium**.

### Final Answer:
The answer is **chemical equilibrium**.

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