 Okay, so let's try this first problem of the day Are you ready? It says, classify each of the following compounds as a strong acid, weak acid, strong base, or weak base And then it gives us these four compounds H2, S, E, O, 4 So this is selenic acid, it's just this carboxylic acid So it's giving you a bunch of kind of information over here But the real portion of the molecule that you want to focus on is the COOH Because remember, if you recall from our last slide, the COOH, that's the carboxylic acid And I don't want to give it away before we start talking The next one is, well, potassium hydroxide And you know this one already from way back in Jenkins 1 And then we've got this amine It's got the same sort of... So it's got all of this, it's just like the same one here, CH So if you look at both this compound and this compound It's got all of this information here, which is part of the molecule in general But since we're just wondering if it's a weak acid or strong acid or weak base or strong base In these compounds we just want to look at this portion of it Well, anyways, selenic acid, hopefully, if you don't remember the rule The ionizable hydrogens to number of oxygens rule You might remember that selenium is in the same family as sulfur So if you remember sulfuric acid, that's one of our strong acids that we've used even in the lab But if you do want to remember that ionizable proton rule It's if the number of oxygens in the molecule exceeds the number of ionizable protons by 2 or more And in this case we have 2 protons or 2 hydrogen atoms and 4 oxygens So that would be 2, right? So, classified, then I guess this would be a strong acid, right? So strong and acid So this one, what do we say about all carboxylic acids or what? They're acids, definitely But what were the, yeah, they're weak acids, why do we know that? Because the strong acids are the hydrohalic acids, right? And these ones that we were just describing The ones that have the oxygens and hydrogens relative to the number of 2, right? Potassium hydroxide, if you recall, anything with the hydroxide in it That's a strong base, right? So don't get confused by these OHs here in the carboxylic acid This is just a kind of a simplified way of writing this thing It doesn't actually have, this is not a hydroxide ion that is ionizable Like in this molecule here In fact, if you want to think about it, this is not bonded this way It's bonded with this carbon here and that oxygen up there So this carbon is actually bonded to that And that's bonded to that, so it looks something like that So if you see, in fact, what's happening is since this is a weak acid It's that proton there that's ionizing, okay? In this case, to have a strong base, remember We have to have the hydroxide ion itself be ionized, okay? So we say this is a strong base we already know Like we said, we know that from, I don't even remember Somewhere in Jim Kim 1 chapter 6 or something like that But when we ionize this thing, right? You put this in water, you get potassium ions and hydroxide ions Like that, but when you put this into water You don't, you get the carboxylate ions here Plus the proton, okay? So that's a difference that a lot of people kind of get confused on Okay, because they see those OH's there and they think it means the same thing So don't let it confuse you, very easy to get confused Okay, and if you recall amines, remember what we said All amines, those are going to be weak bases, okay? Something with a nitrogen and carbons Um, it's a weak base if you don't recall that amine rule It's a weak base because I'm sure you remember from Vesper theory That that nitrogen is bonded to three different atoms, right? So if it's bonded to three atoms, it's going to have that lone pair there Okay, and if you recall anything with a lone pair Is something that can deprotonate an acid, okay? So since this thing has a lone pair and can deprotonate an acid We call that a base, something that deprotonates an acid But it's not a strong base because we don't see that ionized hydroxide ion, okay? So anyways, it's going to be a weak base All amines are weak bases So, any questions? So I guess, let's just write this So this is an amine And this is a, okay? Any questions? No Okay, cool