Which among the following is not obtained by treating aqueous silver nitrate with hypophosphorous acid?

Options

A. `H_3PO_3`
B. `Ag`
C. `HNO_3`
D. `H_3PO_4`

Answer

To solve the question "Which among the following is not obtained by treating aqueous silver nitrate with hypophosphorous acid?", we will analyze the reaction between silver nitrate and hypophosphorous acid step by step.

### Step 1: Identify the Reactants
The reactants in this reaction are:
- Aqueous Silver Nitrate (AgNO3)
- Hypophosphorous Acid (H3PO2)

### Step 2: Write the Reaction
When aqueous silver nitrate reacts with hypophosphorous acid, the following reaction occurs:
\[ \text{AgNO}_3 (aq) + \text{H}_3\text{PO}_2 (aq) \rightarrow \text{Ag} (s) + \text{HNO}_3 (aq) + \text{H}_3\text{PO}_3 (aq) \]

### Step 3: Identify the Products
From the reaction, we can identify the products formed:
- Silver (Ag)
- Nitric Acid (HNO3)
- Phosphorous Acid (H3PO3)

### Step 4: Analyze the Options
Now, we need to determine which of the following products is **not** formed:
1. Silver (Ag)
2. Nitric Acid (HNO3)
3. Phosphorous Acid (H3PO3)
4. Phosphoric Acid (H3PO4)

### Step 5: Conclusion
From our analysis, we see that:
- Silver (Ag) is formed.
- Nitric Acid (HNO3) is formed.
- Phosphorous Acid (H3PO3) is formed.
- **Phosphoric Acid (H3PO4)** is **not** formed in this reaction.

Thus, the correct answer is **Phosphoric Acid (H3PO4)**, which is the product that is not obtained.

### Final Answer:
**Phosphoric Acid (H3PO4)** is not obtained by treating aqueous silver nitrate with hypophosphorous acid.

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