`H_(3)PO_(2)+AgNO_(2) to Ag darr+H_(3)PO_(4)+NO`

Options

A. For disproportionation reaction.
B. For comproportionation reaction.
C. For either intermolecular redox reaction or displacement reaction
D. For either thermal combination redox reaction or thermal decomposition redox reaction.

Answer

To solve the given reaction \( H_3PO_2 + AgNO_2 \rightarrow Ag + H_3PO_4 + NO \) and classify it, we will follow these steps:

### Step 1: Identify the oxidation states of elements in the reactants and products.

1. **For \( H_3PO_2 \)**:
- Let the oxidation state of phosphorus (P) be \( x \).
- The oxidation states of hydrogen (H) is +1 and oxygen (O) is -2.
- The equation for the oxidation states will be:
\[ x + 3(+1) + 2(-2) = 0 \]
\[ x + 3 - 4 = 0 \implies x = +1 \]
- Thus, the oxidation state of phosphorus in \( H_3PO_2 \) is +1.

2. **For \( AgNO_2 \)**:
- The oxidation state of silver (Ag) is +1 (as it is a Group 1 element).
- The oxidation state of nitrogen (N) in \( NO_2 \) is +4 (since O is -2, and there are 2 O atoms).
- Therefore, the oxidation state of Ag in \( AgNO_2 \) is +1.

3. **For \( Ag \)** (product):
- The oxidation state of Ag is 0 (elemental form).

4. **For \( H_3PO_4 \)**:
- Let the oxidation state of phosphorus in \( H_3PO_4 \) be \( y \).
- The equation for the oxidation states will be:
\[ y + 3(+1) + 4(-2) = 0 \]
\[ y + 3 - 8 = 0 \implies y = +5 \]
- Thus, the oxidation state of phosphorus in \( H_3PO_4 \) is +5.

5. **For \( NO \)**:
- The oxidation state of nitrogen (N) is +2 (since O is -2).

### Step 2: Determine the changes in oxidation states.

- In the reaction:
- Phosphorus changes from +1 in \( H_3PO_2 \) to +5 in \( H_3PO_4 \) (oxidation).
- Silver changes from +1 in \( AgNO_2 \) to 0 in \( Ag \) (reduction).
- Nitrogen changes from +4 in \( AgNO_2 \) to +2 in \( NO \) (reduction).

### Step 3: Classify the reaction.

- Since there is both oxidation (phosphorus) and reduction (silver and nitrogen) occurring simultaneously, this reaction is classified as a **redox reaction**.
- Specifically, because the oxidation and reduction processes are happening between different species (not within the same species), it is classified as an **intermolecular redox reaction**.

### Final Answer:
The reaction \( H_3PO_2 + AgNO_2 \rightarrow Ag + H_3PO_4 + NO \) is classified as an **intermolecular redox reaction**.

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