For carbon, we have a lot of carbons and hydrogens here. We can ignore those parts because here's the major force. Hydrogen is connected to nitrogen. Hydrogen bonding is a stronger force than London dispersion. Because it has hydrogen connected to nitrogen here, we're going to say that this is hydrogen bonding. Hydrogen bonding is a polar force. And in this example, we have hydrogen connected to fluorine. This is also hydrogen bonding and it's also a polar force. Both are polar, so they'll definitely make a solution.

Now, one thing we need to talk about here is this compound in carbon has a lot of carbons with it. Let's say we're trying to dissolve a compound that had a lot of carbons in water. What we need to realize here is that the more carbons your compound has, the more nonpolar it becomes. This is an important concept for Chem 1 and also for those of you who are going to take organic 1 and organic 2. We're going to say the more carbons associated with the compound, the more nonpolar it becomes, and the less soluble it becomes in water. The less of it will dissolve to form a solution. We're going to say the cutoff is once you get up to 5 carbons or higher, that compound becomes very nonpolar and it becomes incredibly difficult to dissolve it in water.

So if we're looking at 2 compounds, CH₃CH₂CH₂CH₃ and another compound, and your professor wanted you to determine which one is more soluble in water. We're going to say both have the same number of carbons. Both have 4 carbons. So they are somewhat dissolvable in water. Because water, its intermolecular force is hydrogen bonding. And here, we have hydrogen connected to oxygen. Part of this compound does have hydrogen bonding. That's what makes it soluble somewhat in water.

Now, we're going to say that the second structure is more soluble because the second structure has more oxygens. So the more oxygens you have, the more nitrogens you have, the more hydrogens bonded to fluorine you have, the more hydrogen bonding you'll possess. And the more hydrogen bonding you possess, the more you'll be able to dissolve in water. So if we were comparing these 2, we'd say the second one is more dissolvable in water.

Now, let's say we had CH₃OH or CH₃CH₂OH. Both have oxygen, so both have hydrogen bonding. But the second structure has more carbons, so it's less soluble in water. The top one has hydrogen bonding because of the oxygen and it only has one carbon, so it would be more soluble. So just make a little note on this. The more carbons we have, the more nonpolar. The more oxygens, nitrogens, and hydrogens bonded to fluorine, the more hydrogen bonding you'll possess, and the more soluble you'll be in water.