 So let's do this problem. So it's another one of these ranking the acid strength. So what you can see here is that all three of these acids, hypochlorous acid, hypo bromis acid, and hypoiodic acid, all have the same what we know as oxidation state, okay? So you have an H and an O and the only thing that's different is that halogen okay, so what we're going to think of is which one of those is going to allow the proton to be removed by a base the quickest, okay? So in order to think about it that way, we need to think about the relative electronegativities of these particular acids, okay? So remember electronegativity is the ability for atom to attract itself to electrons, okay? So what we want to look at is, well, what's more electronegative? Chlorine, bromine, or iodine, okay? So if we look at the periodic table, we know that electronegativity goes through the families up, okay? So out of these three, chlorine is more electronegative than bromine, which is more electronegative than iodine, okay? So when we think about it that way, we realize that the chlorine attracts the electrons, so this has OH bond, so it's going to look C, L, O, H, like that, okay? So this chlorine, even though it's far away over here, will attract, we call this an inductive effect, will attract those electrons more so than the bromine will in this structure, okay? And of course more so than the iodine will in this structure, okay? So what we find is that through the inductive effect, the pulling of those electrons due to the electronegativity of these atoms, what we'll find is that this has the greatest inductive effect, this one has a smaller one, and this one has a very small one like that, okay? So this proton will be easily removed by a base, and this one not as easily in this one, and really not as easily as this one, okay? So if we're going to rank these from most acidic to least acidic, we would rank them like this. H, C, L, O is more acidic than H, D, R, O, which is more acidic than H, I, O, like that, okay? Does that make sense? So it's due to the electronegativity. So if you don't remember your electronegativity rules, go back and learn those electronegativity rules. You got this.