When rate of forward reaction becomes equal to backward reaction, this state is termed as

Options

A. Chemical equilibrium
B. Reversible state
C. Equilibrium
D. All of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Reaction Dynamics:**
- In a chemical reaction, reactants are converted into products. The process can be represented as:
\[ A \rightleftharpoons B \]
- Here, A is the reactant that converts into product B.

2. **Forward and Backward Reactions:**
- The forward reaction refers to the conversion of reactants into products (A to B).
- The backward reaction refers to the conversion of products back into reactants (B to A).

3. **Equilibrium Condition:**
- The state where the rate of the forward reaction equals the rate of the backward reaction is termed as "equilibrium."
- At this point, the concentration of reactants and products remains constant over time, although both reactions continue to occur.

4. **Types of Equilibrium:**
- Equilibrium can be classified into two types:
- **Chemical Equilibrium:** This occurs in reactions involving chemical changes, such as the formation of ammonia from nitrogen and hydrogen:
\[ N_2 + 3H_2 \rightleftharpoons 2NH_3 \]
- **Physical Equilibrium:** This occurs in physical processes, such as the melting of ice into water and vice versa.

5. **Conclusion:**
- Therefore, when the rate of the forward reaction becomes equal to the rate of the backward reaction, this state is termed as "equilibrium." It can be referred to as either chemical equilibrium or physical equilibrium depending on the nature of the reaction.

**Final Answer:**
The state is termed as "equilibrium."

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