Heating P2O5 with water results in the formation of orthophosphoric acid (H3PO4). Let's break down the process step by step:

1. P2O5 is a molecular compound known as diphosphorus pentoxide. It is a white, crystalline solid that is highly hygroscopic, meaning it readily absorbs water from the surrounding environment.

2. When P2O5 is exposed to water (H2O), it undergoes a hydrolysis reaction. Hydrolysis is a chemical reaction in which a compound reacts with water to produce new compounds.

3. In the case of P2O5, the hydrolysis reaction can be represented as follows:
P2O5 + 3H2O → 2H3PO4

4. The reaction shows that P2O5 reacts with three molecules of water to form two molecules of orthophosphoric acid (H3PO4). The balanced chemical equation indicates the stoichiometric ratio between P2O5 and H3PO4.

5. Orthophosphoric acid, also known as phosphoric acid, is a weak acid with the chemical formula H3PO4. It is a colorless, viscous liquid that is commonly used in various industries, including food and beverages, fertilizers, and detergents.

Overall, the reaction between P2O5 and water results in the formation of orthophosphoric acid (H3PO4). This reaction is an example of a hydrolysis reaction, where the compound P2O5 reacts with water to produce a different compound. It is important to note that the reaction requires three molecules of water for every molecule of P2O5 to form two molecules of orthophosphoric acid.