`P_(4)O_(10)` is the anhydride of the following 

Options

A. `H_(3)PO_(2)`
B. `H_(3)PO_(3)`
C. `H_(3)PO_(4)`
D. `H_(3)PO_(5)`

Answer

To determine which compound \( P_4O_{10} \) is the anhydride of, we can follow these steps:

### Step 1: Understand the concept of anhydrides
An anhydride is a compound that can be formed by the removal of water from an acid. In this case, we are looking for the acid from which \( P_4O_{10} \) can be derived.

### Step 2: Identify the options given
The options provided are:
- \( S_3PO_2 \)
- \( S_3PO_3 \)
- \( S_3PO_4 \)
- \( S_3PO_5 \)

### Step 3: Analyze the formation of \( P_4O_{10} \)
When phosphorus reacts with oxygen, it forms \( P_4O_{10} \). This reaction can be represented as:
\[ 4P + 5O_2 \rightarrow P_4O_{10} \]

### Step 4: Hydrolysis of \( P_4O_{10} \)
When \( P_4O_{10} \) is hydrolyzed (reacted with water), it forms phosphoric acid, which is \( H_3PO_4 \). The reaction can be represented as:
\[ P_4O_{10} + 6H_2O \rightarrow 4H_3PO_4 \]

### Step 5: Determine the anhydride
Since \( P_4O_{10} \) is formed from the dehydration of \( H_3PO_4 \), we can conclude that:
\[ P_4O_{10} \text{ is the anhydride of } H_3PO_4 \]

### Step 6: Identify the correct option
Among the options, \( S_3PO_4 \) corresponds to \( H_3PO_4 \). Therefore, \( P_4O_{10} \) is the anhydride of \( S_3PO_4 \).

### Final Answer
Thus, the correct answer is:
**C. \( S_3PO_4 \)**

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