 Okay, so let's try this problem, which is a problem that was very similar to the last problem that we did, except the only thing we've done is changed the acid that we're titrating. Okay, and the last problem, we're titrating the cedic acid, and this problem we're titrating phosphoric acid. When we do that, hopefully you see that the equation is balanced differently, right? So we have a 3 to 1 ratio, as opposed to a 1 to 1 ratio like we did in the last problem. And this is going to affect our number. Anyway, so this is the titration problem we're wondering about volume and concentration. So we've got volume here, and we've got concentration of NaOH here. So remember, molarity is moles per liter, so I like to write it like that, so we can use it to convert. And we've got our volume of NaOH, our volume of sodium hydroxide in milliliters, so we want to convert that to liters, so we can cancel the volume now. So that'll cancel out our mill step, giving us 0.0947 liters in NaOH. Okay, everybody's okay with that. And then we've got, so we've got that many liters, we're trying to figure out how many moles of NaOH we've got. So we're going to multiply this conversion factor, the molarity, by what we just got, liters of NaOH. That's going to cancel with that. And going to give us 0, 1. So to that point, we've done the exact same thing as the last problem. So it's at this point where the problems kind of switch gears. So here we, again, we're trying to figure out what's the concentration of this. So we've got the number of moles of this, so we're going to have to use the reaction equation for the mole-to-mol conversion. So in order to find the number of moles of phosphoric acid we needed, so it's three moles of NaOH to one mole of fluoric acid, so we cancel there. So divide that number by three, and we get this number, 6.31 times 10 to the negative third moles of phosphoric acid, like that. So notice this is a different number than what we had before, okay, with the acetic acid problem. So we know how many moles of phosphoric acid we've got, this, the liters, so the volume is the same, too. So how do we do the concentration? Well, it's the number of moles of phosphoric acid divided by the liters of phosphoric acid, so 6.31 times 10 to the negative third moles divided by 0.0250 liters to the negative third mole of phosphoric acid. So hopefully I've proved to you that if you, a reaction equation where you need a different number of equivalents of base to acid, you can't just do that M1B1. Are there any questions on this one? Any questions? Okay, I'm going to kill this one.