Reducing agent are also called __________.

Answer

**Step-by-Step Solution:**

1. **Understanding the Term Reducing Agent:**
- A reducing agent is a substance that donates electrons to another substance in a redox reaction. This process reduces the oxidation state of the other substance while increasing its own oxidation state.

2. **Alternative Name for Reducing Agent:**
- Reducing agents are also known as "reductants." This term highlights their role in the reduction process during chemical reactions.

3. **Example of a Reducing Agent:**
- Consider the reaction between sodium (Na) and chlorine (Cl2) to form sodium chloride (NaCl):
\[ 2 \text{Na} + \text{Cl}_2 \rightarrow 2 \text{NaCl} \]
- In this reaction, sodium starts with an oxidation state of 0 and ends with an oxidation state of +1, indicating that it loses electrons (oxidation).
- Chlorine starts with an oxidation state of 0 and ends with an oxidation state of -1, indicating that it gains electrons (reduction).

4. **Identifying the Reducing Agent:**
- Since sodium donates electrons to chlorine, sodium acts as the reducing agent (or reductant) in this reaction.

5. **Conclusion:**
- Therefore, reducing agents are also called "reductants."

**Final Answer:**
Reducing agents are also called **reductants**.

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