Now, if you don't know what Titration is and you don't know what an equivalence point Is, then check out the link below. So, once again, we're tightrading an acid with the base. And here's our Titration curve where the y axis is PH and the x axis is the volume of base added. Now, we've defined the equivalence point to be the point at which all the acid has been neutralized. So every single molecule of acid in our buffer system has been neutralized. Now, we can also define something called the half equivalence point.