00:01
This problem because it's much easier once you draw out all of the atoms in the compound and seeing where things are actually sitting.
00:09
So once you draw the cis version, this is probably how this is going to sit.
00:15
You can actually form somewhat of a seven -membered ring between the oxygen of one of the carbonyles and the hydrogen of the carboxylic acid of the other.
00:25
So this is heavily bonded intramolecularly, and therefore, you don't have quite as strong of intermolecular interactions as you would with fumaric acid.
00:38
And that is really because one of the oxygens here is hydrogen bonding with itself.
00:44
So this is actually going to pack quite a bit better because you have more intermolecular forces that are not quite as present with malic acid due to this effect.
00:55
That is why the melting point for a fumaric acid is much greater than that of malayic acid.
01:01
In terms of solubility, this can come down to dipole moment.
01:05
So keep in mind, like dissolves like.
01:08
Waters has a pretty great dipole moment.
01:12
Fumaric acid actually isn't going to have an overall dipole because if you look at the directions of the dipole vectors, they're going to cancel each other out to a net dipole of essentially zero.
01:25
But for malayic acid, if we draw the dipole moments, these are now additive and you're going to have a dipole moment in this direction at the end of the day...