Le-Chatelier's principle is applicable only to a

Options

A. System in equilibrium
B. Irreversible reaction
C. Homogeneous reaction
D. Heterogeneous reaction

Answer

**Step-by-Step Solution:**

1. **Understanding Le Chatelier's Principle**: Le Chatelier's Principle states that if an external change is applied to a system at equilibrium, the system will adjust itself to counteract that change and restore a new equilibrium.

2. **Identifying the Conditions**: The principle applies when there are changes in conditions such as temperature, pressure, or concentration of reactants/products in a chemical reaction.

3. **Equilibrium Systems**: Le Chatelier's Principle is specifically applicable to systems that are in a state of equilibrium. This means that the forward and reverse reactions are occurring at the same rate, and the concentrations of reactants and products remain constant.

4. **Analyzing the Options**:
- **System in Equilibrium**: This is the correct answer because Le Chatelier's Principle is used to predict how the system will respond to changes.
- **Irreversible Reaction**: This is incorrect because irreversible reactions do not reach a state of equilibrium.
- **Homogeneous Reaction**: While homogeneous reactions can be in equilibrium, the principle itself is not limited to them.
- **Heterogeneous Reaction**: Similar to homogeneous reactions, heterogeneous reactions can also be in equilibrium, but the principle applies to any equilibrium system.

5. **Conclusion**: The correct answer is that Le Chatelier's Principle is applicable only to a system in equilibrium.

**Final Answer**: Le Chatelier's principle is applicable only to a **system in equilibrium**.

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