`H_(2)S` can be dreid by how many of the following reagents? Anhydrous `CaCl_(2)` conc. `H_(2)SO_(4), P_(2)O_(3), KOH` solutons, `Na_(2)CO_(3)` soluton.

Explanation

To determine how many of the given reagents can dry hydrogen sulfide (H₂S), we need to identify which of the listed substances are drying agents. Let's analyze each reagent step by step.

### Step 1: Identify the reagents
The reagents provided are:
1. Anhydrous CaCl₂
2. Concentrated H₂SO₄
3. P₂O₃
4. KOH solution
5. Na₂CO₃ solution

### Step 2: Analyze each reagent for drying properties
1. **Anhydrous CaCl₂**:
- This is a well-known drying agent. It can absorb moisture from gases and liquids, making it suitable for drying H₂S.
- **Conclusion**: Can dry H₂S.

2. **Concentrated H₂SO₄**:
- This is a dehydrating agent, which means it removes water chemically. While it can absorb moisture, it does not act as a drying agent in the context of drying gases like H₂S.
- **Conclusion**: Cannot dry H₂S.

3. **P₂O₃ (Phosphorus trioxide)**:
- This compound can also act as a drying agent by absorbing water from gases.
- **Conclusion**: Can dry H₂S.

4. **KOH solution**:
- KOH is primarily used as a base and can react with acids but is not typically used as a drying agent for gases. It does not effectively remove moisture from H₂S.
- **Conclusion**: Cannot dry H₂S.

5. **Na₂CO₃ solution**:
- Sodium carbonate is not a drying agent; it is a salt that does not remove moisture from gases.
- **Conclusion**: Cannot dry H₂S.

### Step 3: Count the drying agents
From the analysis:
- Anhydrous CaCl₂: Can dry H₂S (1)
- Concentrated H₂SO₄: Cannot dry H₂S (0)
- P₂O₃: Can dry H₂S (1)
- KOH solution: Cannot dry H₂S (0)
- Na₂CO₃ solution: Cannot dry H₂S (0)

Total drying agents = 2 (Anhydrous CaCl₂ and P₂O₃)

### Final Answer:
H₂S can be dried by **2** of the given reagents.

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