The reversible reaction
`[Cu(NH_(3))_(4)]^(2+)+SO_(3)^(2-)hArr[Cu(NH_(3))_(3)SO_(3)]+NH_(3)`
is at equilibrium. What would not happen if ammonia is added -

Options

A. `[SO_(3)^(2-)]` would increase
B. `[Cu(NH_(3))_(3)SO_(3)]` would increase
C. The value of equilibrium constant would not change
D. `[Cu(NH_(3))_(4)]^(2+)` would increase

Answer

To solve the problem, we need to analyze the reversible reaction given and apply Le Chatelier's principle. The reaction is:

\[ [Cu(NH_3)_4]^{2+} + SO_3^{2-} \rightleftharpoons [Cu(NH_3)_3SO_3] + NH_3 \]

### Step 1: Identify the Effect of Adding Ammonia
When ammonia (NH₃) is added to the system, it will increase the concentration of one of the reactants on the left side of the equilibrium. According to Le Chatelier's principle, the system will respond to counteract this change by shifting the equilibrium position.

### Step 2: Determine the Direction of the Shift
Since we are adding ammonia, the equilibrium will shift to the left to reduce the concentration of ammonia. This means that more of the complex \([Cu(NH_3)_4]^{2+}\) and \(SO_3^{2-}\) will be formed, and the concentration of the products \([Cu(NH_3)_3SO_3]\) and \(NH_3\) will decrease.

### Step 3: Analyze What Will Not Happen
The question asks what will not happen if ammonia is added. Since the equilibrium shifts to the left, the concentration of the product \([Cu(NH_3)_3SO_3]\) will not increase. Instead, it will decrease as the equilibrium shifts to the left.

### Conclusion
Therefore, the correct answer is that the concentration of \([Cu(NH_3)_3SO_3]\) will not increase when ammonia is added.

### Summary of Steps:
1. **Identify the effect of adding ammonia**: Increase in reactant concentration.
2. **Determine the direction of the shift**: Equilibrium shifts to the left.
3. **Analyze what will not happen**: Concentration of \([Cu(NH_3)_3SO_3]\) will not increase.