The pH of a neutral solution, like pure water, is 7.

Here's why:

* pH Scale: The pH scale measures the acidity or alkalinity of a solution. It ranges from 0 to 14.

* Neutral: A neutral solution has an equal concentration of hydrogen ions (H+) and hydroxide ions (OH-).

* Pure Water: Pure water has a very low concentration of both H+ and OH- ions, making it neutral.

* Equilibrium: The pH of pure water is determined by the equilibrium constant for the self-ionization of water, which is 1 x 10^-14 at 25°C. This constant results in a pH of 7.

Important Note: The pH of pure water can slightly vary depending on temperature.