In which of the following reaction, phosphine is not obtained as product

Options

A. `Ca_(3)P_(2)+H_2Oto`
B. `P_(4)+NaOHto`
C. `H_(3)PO_(3)overset(Delta)(to)`
D. None of these

Answer

To determine in which reaction phosphine (PH₃) is not obtained as a product, we will analyze each given reaction step by step.

### Step 1: Analyze the first reaction
**Reaction:** Ca₃P₂ + H₂O → Ca(OH)₂ + PH₃

- In this reaction, calcium phosphide (Ca₃P₂) reacts with water (H₂O) to produce calcium hydroxide (Ca(OH)₂) and phosphine (PH₃).
- **Conclusion:** Phosphine is obtained in this reaction.

**Hint:** Look for the products formed in the reaction to identify if phosphine is produced.

### Step 2: Analyze the second reaction
**Reaction:** P₄ + NaOH + H₂O → NaH₂PO₂ + PH₃

- Here, tetraphosphorus (P₄) reacts with sodium hydroxide (NaOH) in the presence of water (H₂O) to yield sodium hypophosphite (NaH₂PO₂) and phosphine (PH₃).
- **Conclusion:** Phosphine is obtained in this reaction as well.

**Hint:** Check the reactants and products carefully to see if phosphine is listed among the products.

### Step 3: Analyze the third reaction
**Reaction:** H₃PO₃ (phosphorous acid) → H₃PO₄ + PH₃

- In this reaction, when phosphorous acid (H₃PO₃) is heated, it decomposes to form phosphoric acid (H₃PO₄) and phosphine (PH₃).
- **Conclusion:** Phosphine is also obtained in this reaction.

**Hint:** Consider the decomposition reactions and the products formed to determine if phosphine is produced.

### Final Conclusion
After analyzing all three reactions, we find that phosphine is produced in all of them. Therefore, the answer to the question "In which of the following reactions is phosphine not obtained as a product?" is:

**Answer:** None of these reactions yield phosphine as a product.