Which of the following is most reducing agent

Options

A. `HNO_(3)`
B. Na
C. `Cl_(2)`
D. Cr

Answer

To determine which of the given options is the most effective reducing agent, we will analyze each option based on their properties as reducing agents.

### Step-by-Step Solution:

1. **Identify the Options**: The options provided are HNO3, Sodium (Na), Chlorine (Cl2), and Chromium (Cr).

2. **Classify Each Compound**:
- **HNO3 (Nitric Acid)**: This is known to be a strong oxidizing agent. It tends to gain electrons rather than lose them, which means it cannot act as a reducing agent.
- **Sodium (Na)**: Sodium is an alkali metal that readily loses an electron to form Na+. This characteristic makes it a strong reducing agent.
- **Chlorine (Cl2)**: Chlorine is a diatomic molecule that acts as an oxidizing agent. It gains electrons to form Cl- ions, thus it cannot be a reducing agent.
- **Chromium (Cr)**: While chromium can act as a reducing agent in certain compounds, it is generally not as strong a reducing agent as sodium.

3. **Compare the Reducing Strength**:
- **HNO3**: Not a reducing agent (oxidizing agent).
- **Sodium**: Strong reducing agent due to its ability to easily lose an electron.
- **Chlorine**: Not a reducing agent (oxidizing agent).
- **Chromium**: Moderate reducing agent, but weaker than sodium.

4. **Conclusion**: Among the options, Sodium (Na) is the strongest reducing agent as it readily donates electrons.

### Final Answer:
The most reducing agent among the given options is **Sodium (Na)**.

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