What is waters equilibrium expression?

The equilibrium expression for water, specifically for its autoionization, is represented by the equation ( K_w = [H^+][OH^-] ), where ( K_w ) is the ion product of water at a given temperature. At 25°C, ( K_w ) is approximately ( 1.0 \times 10^{-14} ). This expression illustrates the relationship between the concentrations of hydrogen ions (( H^+ )) and hydroxide ions (( OH^- )) in pure water, indicating that as one increases, the other decreases to maintain equilibrium.