The formation of ADP and inorganic phosphate from ATP and water is an example of a hydrolysis reaction.

Here's why:

* Hydrolysis means "breaking down with water." In this case, a water molecule (H₂O) is used to break the bond between the phosphate groups in ATP.

* The water molecule provides a hydroxyl group (OH-) that attaches to one phosphate group, and a hydrogen ion (H+) that attaches to the remaining portion of the ATP molecule, forming ADP and inorganic phosphate (Pi).

The reaction can be written as:

ATP + H₂O → ADP + Pi

This reaction is exergonic, meaning it releases energy. This energy is what cells use to perform various functions.