`P_2 O_5` is heated with water to give

Options

A. Hypophosphorus acid
B. Orthophosphorus acid
C. Hypophosphoric acid
D. Orthophosphoric acid

Explanation

To solve the question of what happens when \( P_2O_5 \) is heated with water, we can follow these steps:

### Step 1: Identify the Reactants
The reactants in this reaction are \( P_2O_5 \) (phosphorus pentoxide) and water (\( H_2O \)).

### Step 2: Write the Reaction
When \( P_2O_5 \) is heated with water, it reacts to form phosphoric acid. The unbalanced chemical equation can be written as:
\[ P_2O_5 + H_2O \rightarrow H_3PO_4 \]

### Step 3: Balance the Reaction
To balance the reaction, we need to ensure that the number of atoms of each element is the same on both sides of the equation. The balanced equation is:
\[ P_2O_5 + 3H_2O \rightarrow 2H_3PO_4 \]

### Step 4: Identify the Product
The product formed from this reaction is \( H_3PO_4 \), which is known as orthophosphoric acid.

### Step 5: Understand the Significance
Orthophosphoric acid is significant because it contains phosphorus in its maximum oxidation state of +5. This is important in various chemical applications and reactions.

### Final Answer
When \( P_2O_5 \) is heated with water, it produces orthophosphoric acid (\( H_3PO_4 \)).

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