The substance that loses electrons is called as

Options

A. oxidizing agent
B. reducing agent
C. catalyst
D. none of above

Answer

**Step-by-Step Solution:**

1. **Understanding the Terms:**
- To determine what we call a substance that loses electrons, we first need to understand some key terms in chemistry related to oxidation and reduction.

2. **Oxidizing Agent:**
- An oxidizing agent is a substance that causes oxidation in another substance. This means it facilitates the loss of electrons from that substance. However, the oxidizing agent itself undergoes reduction, meaning it gains electrons.

3. **Reducing Agent:**
- A reducing agent, on the other hand, is a substance that causes reduction in another substance. This means it facilitates the gain of electrons by that substance. In the process, the reducing agent itself undergoes oxidation, which means it loses electrons.

4. **Identifying the Substance that Loses Electrons:**
- Since we are looking for the term that describes a substance that loses electrons, we refer to the definition of a reducing agent. By definition, a reducing agent is the substance that donates electrons to another substance, thereby causing that substance to be reduced.

5. **Conclusion:**
- Therefore, the substance that loses electrons is called a **reducing agent**.

**Final Answer:**
The substance that loses electrons is called a **reducing agent**.

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