Here's why:

* Ions are atoms or molecules that have gained or lost electrons, giving them a net electrical charge.

* Water is a neutral molecule. It has two hydrogen atoms (H) and one oxygen atom (O) bonded together, with a balanced number of protons and electrons.

However, water can dissociate into ions under certain conditions:

* When water dissolves in solution: A small fraction of water molecules break apart into hydrogen ions (H⁺) and hydroxide ions (OH⁻). This process is called auto-ionization of water.

* When acids or bases are added to water: Acids release H⁺ ions, while bases release OH⁻ ions. This changes the pH of the water.

In summary: While water itself is not an ion, it can form ions through dissociation.