If an iron rod is dipped in `CuSO_(4)` solution

Options

A. Blue colour of the solution turns green
B. Brown layer is deposited on iron rod
C. No change occurs in the colour of the solution
D. Blue colour of the solution vanishes

Explanation

To solve the question of what happens when an iron rod is dipped in a CuSO4 (copper(II) sulfate) solution, we can analyze the chemical reaction that occurs step by step.

### Step 1: Identify the Components
When an iron rod is dipped in a CuSO4 solution, we have two main components:
- Iron (Fe) from the iron rod.
- Copper(II) sulfate (CuSO4) in the solution.

### Step 2: Understand the Reaction
Iron is more reactive than copper. Therefore, when the iron rod is placed in the CuSO4 solution, a displacement reaction occurs. The iron displaces the copper from the copper sulfate solution.

### Step 3: Write the Chemical Equation
The reaction can be represented by the following equation:
\[ \text{Fe (s)} + \text{CuSO}_4 (aq) \rightarrow \text{FeSO}_4 (aq) + \text{Cu (s)} \]

### Step 4: Analyze the Color Change
- The CuSO4 solution is blue in color due to the presence of copper ions (Cu²⁺).
- As the reaction proceeds, copper ions are reduced to solid copper (Cu), which precipitates out of the solution.
- The iron ions (Fe²⁺) are formed in the solution, which gives the solution a greenish color (due to the formation of iron(II) sulfate).

### Step 5: Conclusion
Based on the above analysis:
1. The blue color of the CuSO4 solution changes to green as the reaction occurs.
2. A brown layer of copper is deposited on the iron rod.
3. The blue color does not completely vanish; instead, it changes to green.

Thus, the correct answer is that the blue color of the solution turns green.

### Final Answer
The blue color of the solution turns green.

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