A reducing agent is a substance which can

Options

A. accept electrons
B. donate electrons
C. accept protons
D. donate protons.

Answer

To answer the question "A reducing agent is a substance which can...", we need to understand the definitions of oxidation, reduction, and the role of a reducing agent in a redox reaction. Here’s a step-by-step solution:

### Step 1: Define Oxidation and Reduction
- **Oxidation** is defined as the loss of electrons by a substance.
- **Reduction** is defined as the gain of electrons by a substance.

### Step 2: Understand the Role of a Reducing Agent
- A **reducing agent** is a substance that causes another substance to be reduced (gain electrons) while itself gets oxidized (loses electrons).
- Therefore, the reducing agent donates electrons to the other species.

### Step 3: Analyze the Options
- The options given are:
1. Accept electrons
2. Donate electrons
3. Accept protons
4. Donate protons

### Step 4: Identify the Correct Option
- Since a reducing agent donates electrons to reduce another species, the correct answer is:
- **Donate electrons** (Option 2).

### Conclusion
A reducing agent is a substance that donates electrons to another substance, thereby reducing it while itself being oxidized.

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