What products are formed when `H_(3)PO_(2)` is heated at `415 K` and at `435 K` respectively.

Answer

To determine the products formed when H₃PO₂ (phosphorous acid) is heated at two different temperatures (415 K and 435 K), we can analyze the thermal decomposition of H₃PO₂.

### Step-by-Step Solution:

1. **Identify the Compound**: We start with H₃PO₂, which is known as phosphorous acid.

2. **Heating at 415 K**: When H₃PO₂ is heated at 415 K, it decomposes to form:
- Phosphine (PH₃)
- Phosphoric acid (H₃PO₄)

The reaction can be represented as:
\[ \text{H}_3\text{PO}_2 \rightarrow \text{PH}_3 + \text{H}_3\text{PO}_4 \]

3. **Heating at 435 K**: When H₃PO₂ is heated at 435 K, it also decomposes, but the products formed are:
- Phosphine (PH₃)
- Phosphorous acid (H₃PO₃)

The reaction can be represented as:
\[ \text{H}_3\text{PO}_2 \rightarrow \text{PH}_3 + \text{H}_3\text{PO}_3 \]

4. **Summary of Products**:
- At **415 K**, the products are **PH₃** and **H₃PO₄**.
- At **435 K**, the products are **PH₃** and **H₃PO₃**.

### Final Answer:
- When heated at **415 K**: PH₃ (phosphine) and H₃PO₄ (phosphoric acid).
- When heated at **435 K**: PH₃ (phosphine) and H₃PO₃ (phosphorous acid).