So remember, liquids are not included. Only eighthway solutions are included. So our KWR constant is equal to the concentration of hydronium times the concentration of hydroxide. So kw in this case, when we talk about autoionization, is called the ionization constant for H 20. And this depends on temperature. And at 25 degrees Celsius, you should know that kw is 1.0 times ten to negative 14.