How many moles of hypophosphorous acid are involved in its thermal decomposition reaction when one mole of each product is formed.

Explanation

To solve the problem of how many moles of hypophosphorous acid (H3PO2) are involved in its thermal decomposition reaction when one mole of each product is formed, we can follow these steps:

### Step 1: Write the thermal decomposition reaction
The thermal decomposition of hypophosphorous acid can be represented as:
\[ \text{H}_3\text{PO}_2 \rightarrow \text{PH}_3 + \text{H}_3\text{PO}_4 \]

### Step 2: Identify the products
From the reaction, we can see that the products formed are:
- Phosphine (PH3)
- Phosphoric acid (H3PO4)

### Step 3: Count the atoms in the products
Now, we need to count the number of atoms of each element in the products:
- Phosphine (PH3) has 1 phosphorus (P) and 3 hydrogens (H).
- Phosphoric acid (H3PO4) has 1 phosphorus (P), 3 hydrogens (H), and 4 oxygens (O).

### Step 4: Balance the reaction
To balance the reaction, we need to ensure that the number of each type of atom is equal on both sides of the equation.

- On the product side, we have:
- Total P = 1 (from PH3) + 1 (from H3PO4) = 2 P
- Total H = 3 (from PH3) + 3 (from H3PO4) = 6 H
- Total O = 4 (from H3PO4) = 4 O

To balance this, we need to adjust the coefficients of H3PO2 on the reactant side.

### Step 5: Write the balanced equation
To balance the reaction, we multiply H3PO2 by 2:
\[ 2 \text{H}_3\text{PO}_2 \rightarrow \text{PH}_3 + \text{H}_3\text{PO}_4 \]

Now, we check:
- On the reactant side:
- Total P = 2 (from 2 H3PO2)
- Total H = 6 (from 2 H3PO2)
- Total O = 4 (from 2 H3PO2)

This matches the product side:
- Total P = 2
- Total H = 6
- Total O = 4

### Step 6: Conclusion
Thus, the balanced equation shows that **2 moles of hypophosphorous acid (H3PO2)** are involved in the thermal decomposition reaction when **1 mole of phosphine (PH3)** and **1 mole of phosphoric acid (H3PO4)** are formed.

### Final Answer:
**2 moles of hypophosphorous acid are involved in the reaction.**

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