Chemistry
Advanced

Water Ion Product

Self-ionization constant of water at 25°C.

Formula

Kw=[H+][OH−]=10−14K_w = [H^+][OH^-] = 10^{-14}

Variables

[H^+]Hydrogen ions
[OH^-]Hydroxide ions

Example

Constant in aqueous solutions

Did You Know?

Even pure water faintly self-ionises, and that constant, Kw, is what fixes neutral pH at exactly 7.

acid-base