And what that means is, based by this calculation, the concentration of the hydrogen ion at a PH of seven is equal to one times ten to negative seven. So now that we know equation B and we know what this value is, we can plug that into this equation and solve for the concentration of the hydroxide ion. And so if we plug that in we get 1.0 times ten to negative 14 is equal to. So now we know what this value is. It's 1.0 times ten to negative seven. And we're looking for this concentration.