When orthophosphoric acid is strongly heated the product formed is

Options

A. Phosphine, `PH_(3)`
B. Phosphorus trioxide, `P_(2)O_(3)`
C. Phosphorous acid, `H_(3)PO_(3)`
D. Metaphosphoric acid, `HPO_(3)`

Answer

To solve the question regarding the product formed when orthophosphoric acid is strongly heated, we can follow these steps:

### Step 1: Identify the chemical formula of orthophosphoric acid
Orthophosphoric acid is also known as phosphoric acid, and its chemical formula is H₃PO₄.

### Step 2: Understand the heating process
When orthophosphoric acid (H₃PO₄) is strongly heated, typically at around 600 degrees Celsius, it undergoes a dehydration reaction.

### Step 3: Write the reaction
Upon strong heating, orthophosphoric acid loses a molecule of water (H₂O) and converts to met phosphoric acid (HPO₃). The reaction can be represented as:
\[ H₃PO₄ \rightarrow HPO₃ + H₂O \]

### Step 4: Identify the product
The product formed from the strong heating of orthophosphoric acid is met phosphoric acid (HPO₃).

### Step 5: Conclusion
Thus, the correct answer to the question is that when orthophosphoric acid is strongly heated, the product formed is met phosphoric acid (HPO₃).

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