So now we know what this value is. It's 1.0 times ten to negative seven. And we're looking for this concentration. So we solve for that and we see that this is also equal to 1.0 times ten to negative seven. So we see that if the PH is equal to seven and we're at room temperature, then the concentration of the hydroxide ion is equal to the concentration of the hydrogen ion. And at this particular moment in time the solution is said to be neutral because the two concentrations are equal.