 So this next problem says identify the conjugate acid base pairs in the following environmental process So here we have the reaction written out for you, notice it's an equilibrium When we're doing this, we want to identify species that are on either side of the reaction that only differ from each other by an H+, okay? So I think that's the best way to think about it, and when you do that, after you do that kind of connect those, okay, or at least that's what I like to do So I'm going to kind of speed us along through this process, this is the first one you guys are seeing But here I see H2PO4 minus, okay, and I want to go to the other side of the reaction and look for something that looks fairly similar to that, okay? So like I said, without an H+, or with an extra H+, okay, depending on whether it's the conjugate acid or the base, okay? So if I look over here, it says HPO4 2 minus, okay? So that is very similar to that, and if I look really closely, I can see definitely that they're only difference at least by an H, and then if I look at that charge, yeah, that's different by a plus, right? So this is this, subtract a plus from that, and you get 2 minus, okay? Or add a plus to that, and you get 1 minus there, okay? So I'm going to connect those two species, okay? So since we only have two more species, those two must be connected as well So typically what we do is, well, let's identify which one is the conjugate acid and conjugate base for the PO4s, okay? So here we have H2PO4, and here we have H2PO4 minus, and here we have HPO4 2 minus. So which one would be the acid component of this? The H2PO4 minus, right? Why? Because it's got one more proton, okay? So we typically, when we're doing these problems, we'll call the things on the reactant side, the acid in the base, and the things on the product side, their conjugate acid and conjugate base. So since this one is the acid and it's on the reactant side, we'll say this is the acid, okay? And this is its conjugate base. Do you understand where I'm going with that? Okay. We could do the same process with these two things, but we know that acids react with bases, right? So since this is an acid, this must be a base, okay? So this is the base. Since this is a base, this must be its conjugate acid. And just to check yourself, because it's good to not just go by these rules, it's good to check yourself, right? So just to check yourself, you want to look and see, well, is this really the acid and this is the base? Well, if I look at this, I have HCO3 minus, and here I have CO3 2 minus, okay, or the bicarb relative to the carbonate ion, okay? So what has happened here? We've lost an H and a plus, right? So that definitely is the conjugate acid of this base, okay? So acid reacts with base on the reactant side, producing their conjugate acid and conjugate base on the product side. Does that make sense? Mm-hmm. Are there any questions on this one? If you had just, if you just have CO3 2 minus, would you just call, would you call that a base normally? Yeah, so that's definitely, so that's the carbonate ion. So in fact, a lot of times in the lab you'll see this in your acid spill kit, as sodium carbonate will be that white granular material that you've seen me throw on some more concentrated acid spill that bubbles up, you know? So in fact, when you do that, it releases carbon dioxide, that's not this reaction here. And then the bicarbonate, you would call an acid, if you just thought of it by yourself? Well, it's also, honestly, it's also basic. In fact, it's a conjugate, but it's the conjugate acid of this base, but it's a conjugate base of another thing, which is carbonic acid, which would be this plus H plus, right? So if you want to think about that, well, what would be the conjugate? H2CO3? Yeah, it'd be H2CO3. That's carbonic acid, and you remove one of the protons, okay? So this is acidic, right? Remove one of the protons you get the bicarbonate ion, which is basic relative to this, but not as basic as this thing, but it is the conjugate acid of this, because why? Because there's two ionizable protons on this, okay? Would that be a strong acid or a weak acid from our O-stages rule? Why? Because we said it had to have two or more oxygens, right? And this one only has one or more, so this is a weak acid. Anyways.