Inert gas has been added to the following equilibrium system at constant volume
`SO_(2)(g)+1//2 O_(2)(g) hArr SO_(3)(g)`
To which direction will the equilibrium shift?

Options

A. Forward
B. Backward
C. No effect
D. Unpredictable

Explanation

To determine the effect of adding an inert gas to the equilibrium system at constant volume, we can follow these steps:

### Step 1: Understand the Equilibrium System
The equilibrium system given is:
\[ \text{SO}_2(g) + \frac{1}{2} \text{O}_2(g) \rightleftharpoons \text{SO}_3(g) \]
This reaction involves the conversion of sulfur dioxide and oxygen into sulfur trioxide.

### Step 2: Apply Le Chatelier's Principle
Le Chatelier's Principle states that if a system at equilibrium is subjected to a change in concentration, temperature, or pressure, the system will adjust to counteract that change and restore a new equilibrium.

### Step 3: Analyze the Effect of Adding an Inert Gas
When an inert gas is added to a system at constant volume, it does not change the concentration of the reactants or products because the volume remains the same. The partial pressures of the gases involved in the equilibrium do not change.

### Step 4: Conclusion
Since the addition of an inert gas at constant volume does not affect the concentrations or partial pressures of the reactants and products, there will be **no shift in the equilibrium position**.

Thus, the correct answer is:
**No effect.**

### Summary of Steps:
1. Identify the equilibrium system.
2. Apply Le Chatelier's Principle.
3. Consider the effect of adding an inert gas at constant volume.
4. Conclude that there is no shift in equilibrium.

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