The following compounds can all react as acids. CH3COOH

Question

CF3COOOH

CF3CH2COOH <

CH3CH2OH

a. For each compound, show its conjugate base. Show any resonance forms if applicable. b. Rank the conjugate bases in the order you would predict, from most stable to least stable.

Accepted Answer

Hey everyone. Let's do this problem. It says draw the structures of conjugate bases for the following acids and we have methane style methane style propranolol? Right? Three carbons and an O. H. Group and formic acid which is a carb oxalic acid. Right? So I'll say compound A. B and C. Why not draw any resonance forms if applicable? And arrange the conjugate bases from the least stable to the most stable. So we're given the acid and it says to arrange the conjugate bases in order of stability. So how do we get a conjugate base from an acid? Well, we know that acids donate a proton and that remaining structure without the proton is the conjugate base. So let's draw our acids and take away one of their protons. So we have methane tile. And when you get rid of that proton, you're just left with an S minus on the end there and it says draw any resonance forms if applicable. Does this structure? Does this conjugate base have any resonance? No there's no pi bonds. Right? There's no M. D. P orbital's next to that negative charge. So there will be no resonance forms here. No resonance forms. So sad. So that's our conjugate base. Alright, let's see our next acid propane all probe. And again we're just removing that proton and we're removing it from the oxygen because that oxygen is more electro negative than these carbons. Right? So that oxygen will be more stable to hold the negative charge when we remove the proton. So we have oh minus there on the end. Now does this have any resonance forms? No it looks pretty similar to this one. Right, there's no empty p orbital zero pi bonds. So it will not have any resonance forms. And lastly, let's look at formic acid, which is a carb oxalic acid with an H. There on the other side of the carbon. So I have this hydrogen and this hydrogen on the O. H. Group. Which one is going to dip, rotate. Well, like I just said in compound B this proton on the oxygen when it D protein eights here, the oxygen is more stable than having a negative carbon, right? Having a negative charge on the carbon. So. Well, D pro Nate at the oxygen Oh minus. And does this have any resonance forms? Yes, I see a negative charge next to a pi bond. So those electrons can swing here, the pi bond electrons go up onto that other oxygen to give us another form where the double bond has moved in, That negative charge has moved to the other oxygen and that's as far as we can go there. So we've drawn all the resonance forms for the conjugate bases that we could. Now let's arrange them from least able to most stable. And again, we're looking at the base is not the conjugate the conjugate base is not the acid. So if we have leased stable conjugate base most stable conjugate base. So what makes a conjugate base stable? Well, we know resonance does right resonance forms d localized those negative charges around the rest of the molecule the compound. So compound cr formic acid, the conjugate base of the formic acid rather is the only one that has resonance. So that will be our most stable conjugate base here. So let's draw that one more time. Okay, now which one is the next most stable? They look pretty similar. Right? The negative charge on the S the negative charge in the O. Well, sulfur is a larger molecule, right? A larger atom. Rather it has a larger radius so it's more polarized herbal and that will make it hold the charge more easily. So that will be our next most stable conjugate base, The one from Methane dial. Okay. Which leaves our conjugate base of propane all as the least stable. Okay, that's it for this problem. I hope this was helpful. And thanks for watching

The following compounds can all react as acids. CH3COOH CF3COOOH CF3CH2COOH < CH3CH2OH a. For each compound, show its conjugate base. Show any resonance forms if applicable. b. Rank the conjugate bases in the order you would predict, from most stable to least stable.

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The following compounds can all react as acids. CH3COOH
CF3COOOH
CF3CH2COOH <
CH3CH2OH
a. For each compound, show its conjugate base. Show any resonance forms if applicable. b. Rank the conjugate bases in the order you would predict, from most stable to least stable.