Phosphorus pentoxide is :

Options

A. oxidising agent
B. reducing agent
C. bleaching agent
D. dehydrating agent

Answer

To determine what phosphorus pentoxide (P4O10) is, we can analyze the options provided in the question step by step.

### Step 1: Understanding the Options
1. **Oxidizing Agent**: An oxidizing agent is a substance that gains electrons in a chemical reaction and is reduced.
2. **Reducing Agent**: A reducing agent is a substance that loses electrons in a chemical reaction and is oxidized.
3. **Bleaching Agent**: A bleaching agent is a substance that can whiten or decolorize other substances.
4. **Dehydrating Agent**: A dehydrating agent is a substance that removes water from other materials.

### Step 2: Analyzing Phosphorus Pentoxide
Phosphorus pentoxide (P4O10) is known for its strong affinity for water. It can effectively remove water from various substances, which is a characteristic of a dehydrating agent.

### Step 3: Conclusion
Given the properties of phosphorus pentoxide, we can conclude that it is primarily a dehydrating agent. Therefore, the correct answer to the question "Phosphorus pentoxide is:" is:

**Dehydrating Agent.**

### Final Answer:
Phosphorus pentoxide is a dehydrating agent.

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