Another ion that would behave similar to `Al^(+3)(aq)` in forming an acidic solution is :

Options

A. `Be_((aq))^(2+)`
B. `Ba_((aq))^(2+)`
C. `Na^+`
D. `Tl^(-)`

Explanation

To determine another ion that behaves similarly to \( \text{Al}^{3+}(aq) \) in forming an acidic solution, we can follow these steps:

### Step 1: Understand the behavior of \( \text{Al}^{3+} \) in solution
- When aluminum chloride (\( \text{AlCl}_3 \)) is dissolved in water, the \( \text{Al}^{3+} \) ions undergo hydrolysis. This means they react with water to produce \( \text{Al(OH)}_3 \) and release \( \text{HCl} \), resulting in an acidic solution.

### Step 2: Identify the characteristics of similar ions
- Ions that can behave similarly to \( \text{Al}^{3+} \) typically have a high charge density and a strong polarizing power. This allows them to attract water molecules and undergo hydrolysis effectively.

### Step 3: Consider other metal ions
- Analyzing other metal ions, we notice that \( \text{Be}^{2+} \) (from beryllium) has a similar high charge density and polarizing power. It can also undergo hydrolysis when dissolved in water, leading to the formation of \( \text{Be(OH)}_2 \) and releasing \( \text{HCl} \), thus making the solution acidic.

### Step 4: Conclusion
- Therefore, the ion that would behave similarly to \( \text{Al}^{3+}(aq) \) in forming an acidic solution is \( \text{Be}^{2+}(aq) \).

### Final Answer
The correct answer is \( \text{Be}^{2+}(aq) \).

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