The agent that keeps maetals in the soluble state is called

Options

A. chelating agent
B. balancing agent
C. buffer agent
D. catalytic agent.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of the agent that keeps metals in a soluble state.

2. **Analyzing the Options**:
- **Option A: Chelating agent** - These agents bind to metal ions and keep them soluble in solution.
- **Option B: Balancing agent** - These agents are used to balance oxidation and reduction reactions, not specifically related to solubility of metals.
- **Option C: Buffer agent** - Buffers are used to maintain the pH of a solution, not to keep metals soluble.
- **Option D: Catalytic agent** - Catalysts speed up reactions without being consumed, but do not specifically relate to metal solubility.

3. **Identifying the Correct Answer**: Based on the definitions and functions of the agents listed, the chelating agent is the only one that specifically keeps metals in a soluble state.

4. **Conclusion**: Therefore, the correct answer is **Option A: Chelating agent**.

5. **Example of Chelating Agent**: A common example of a chelating agent is EDTA (Ethylenediaminetetraacetic acid), which effectively binds metal ions and keeps them soluble.

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