The answer to each of the following questions is a non- negative integer.
Among the following, the number of compounds that can act as dehydrating agent is
`Conc H_2SO_4,anhyd.CaCl_2,conc.HNO_3,CaO,CuSO_4.5H_2O,P_2O_5`

Answer

To determine the number of compounds that can act as dehydrating agents from the given list, we will analyze each compound one by one.

### Step 1: Identify the Compounds
The compounds given are:
1. Conc H₂SO₄ (Concentrated Sulfuric Acid)
2. Anhydrous CaCl₂ (Anhydrous Calcium Chloride)
3. Conc HNO₃ (Concentrated Nitric Acid)
4. CaO (Calcium Oxide)
5. CuSO₄·5H₂O (Copper(II) Sulfate Pentahydrate)
6. P₂O₅ (Phosphorus Pentoxide)

### Step 2: Analyze Each Compound
- **Conc H₂SO₄**: This is a strong dehydrating agent. It can remove water from other substances.

- **Anhydrous CaCl₂**: This is also a dehydrating agent. It can absorb moisture from the air and other compounds.

- **Conc HNO₃**: Concentrated Nitric Acid can act as a dehydrating agent due to its strong oxidizing properties, although it is primarily known for its oxidizing capabilities.

- **CaO**: Calcium Oxide is a dehydrating agent as it reacts with water to form Ca(OH)₂, thus removing water from other substances.

- **CuSO₄·5H₂O**: This is a hydrated salt and does not act as a dehydrating agent. Instead, it can release water upon heating but does not remove water from other compounds.

- **P₂O₅**: Phosphorus Pentoxide is a very strong dehydrating agent and can remove water from various substances.

### Step 3: Count the Dehydrating Agents
From the analysis:
1. Conc H₂SO₄ - Yes
2. Anhydrous CaCl₂ - Yes
3. Conc HNO₃ - Yes
4. CaO - Yes
5. CuSO₄·5H₂O - No
6. P₂O₅ - Yes

### Conclusion
The total number of compounds that can act as dehydrating agents is 5.

### Final Answer
The number of compounds that can act as dehydrating agents is **5**.

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