So we use something called the PH. And the PH is nothing more than a fancy way of determining what the concentration is of our solution. So the PH is equal to negative log of the hydrogen ion concentration in that solution. So if we know what the PH is, then we can easily calculate what the concentration of the hydrogen ion in solution is. For example, if you know that the PH is equal to seven at room temperature. Then you can use this and a bit of algebra to calculate what the concentration is.