In the reaction `HNO_(3)+P_(4)O_(10) to 4HPO_(3)+x `, the product x is

Options

A. `N_(2)O_(3)`
B. `N_(2)O_(5)`
C. `NO_(2)`
D. `H_(2)O`

Explanation

To solve the reaction \( HNO_3 + P_4O_{10} \to 4HPO_3 + x \), we need to identify the product \( x \).

### Step-by-Step Solution:

1. **Identify the Reactants**:
The reactants in the equation are nitric acid (\( HNO_3 \)) and phosphorus pentoxide (\( P_4O_{10} \)).

2. **Rewrite Phosphorus Pentoxide**:
Recognize that \( P_4O_{10} \) can be expressed as \( 2P_2O_5 \). This helps in understanding the stoichiometry of phosphorus in the reaction.

3. **Determine the Reaction**:
When \( HNO_3 \) reacts with \( P_4O_{10} \), it forms phosphoric acid (\( HPO_3 \)). Each molecule of \( P_4O_{10} \) can react with nitric acid to produce \( HPO_3 \).

4. **Balance the Reaction**:
The balanced equation shows that 4 moles of \( HPO_3 \) are produced from the reaction. Therefore, we can write:
\[ HNO_3 + P_4O_{10} \to 4HPO_3 + x \]

5. **Identify the By-product**:
In this reaction, the nitrogen from \( HNO_3 \) will be converted into a nitrogen oxide. The nitrogen oxides formed from nitric acid are typically \( N_2O_5 \) (dinitrogen pentoxide).

6. **Final Equation**:
Thus, the complete balanced reaction can be written as:
\[ 4HNO_3 + P_4O_{10} \to 4HPO_3 + N_2O_5 \]
Here, \( x \) is identified as \( N_2O_5 \).

### Conclusion:
The product \( x \) in the reaction \( HNO_3 + P_4O_{10} \to 4HPO_3 + x \) is \( N_2O_5 \).