A reducing agent is a substance which can

Options

A. Accept electron
B. Donate electron
C. Reduce itself
D. Oxidises another species

Answer

To answer the question, "A reducing agent is a substance which can...", we need to understand the definition and characteristics of a reducing agent in chemistry.

### Step-by-Step Solution:

1. **Definition of a Reducing Agent**:
A reducing agent (or reductant) is a substance that donates electrons to another substance in a chemical reaction. In doing so, it reduces that substance while itself getting oxidized.

2. **Understanding Oxidation and Reduction**:
- **Oxidation** is the process where a substance loses electrons.
- **Reduction** is the process where a substance gains electrons.
Therefore, when a reducing agent donates electrons, it is oxidized itself.

3. **Role of Reducing Agents**:
The primary role of a reducing agent is to facilitate the reduction of another substance. This means that while the reducing agent donates electrons (and thus gets oxidized), it allows another substance to gain those electrons (and thus get reduced).

4. **Examples of Reducing Agents**:
Common examples of reducing agents include hydrogen gas (H₂), carbon monoxide (CO), and metals like zinc (Zn) and iron (Fe). These substances can donate electrons to other substances, leading to their reduction.

5. **Conclusion**:
Therefore, a reducing agent is a substance that can donate electrons to another substance, causing the other substance to be reduced while it itself is oxidized.

### Final Answer:
A reducing agent is a substance which can donate electrons to another substance, causing the other substance to be reduced while it itself is oxidized.

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