Which of the following gives `PH_3` on treatment with water ?

Options

A. `Ca_3P_2`
B. `Na_3P`
C. AlP
D. All of the above

Answer

To solve the question of which of the following compounds gives PH₃ (phosphine) when treated with water, we will analyze each option systematically.

### Step-by-Step Solution:

1. **Understanding Phosphides**:
- Phosphides are compounds that contain phosphorus in a negative oxidation state. When they react with water, they typically produce phosphine (PH₃) and a hydroxide of the metal involved.

2. **Analyzing Each Option**:
- **Option A: Ca₃P₂ (Calcium Phosphide)**
- When Ca₃P₂ reacts with water, the reaction can be written as:
\[ Ca_3P_2 + 6H_2O \rightarrow 2PH_3 + 3Ca(OH)_2 \]
- This shows that Ca₃P₂ produces PH₃ upon treatment with water.

- **Option B: Na₃P (Sodium Phosphide)**
- The reaction of Na₃P with water is:
\[ Na_3P + 3H_2O \rightarrow PH_3 + 3NaOH \]
- This indicates that Na₃P also produces PH₃ when treated with water.

- **Option C: AlP (Aluminum Phosphide)**
- The reaction of AlP with water is:
\[ AlP + 3H_2O \rightarrow PH_3 + Al(OH)_3 \]
- This confirms that AlP also yields PH₃ upon reaction with water.

3. **Conclusion**:
- Since all three compounds (Ca₃P₂, Na₃P, and AlP) produce PH₃ when treated with water, we conclude that the correct answer is:
- **Option D: All of the above.**

### Final Answer:
**Option D: All of the above.**