Question

Draw all the possible triacylglycerols that can be constructed from glycerol, palmitic acid, and oleic acid. Rank them in order of increasing melting point. Hint: There are six ( OOO,OOP,OPO,OPP,POP,PPP) I just need the drawing

Answer 1

Because of the unsaturation in oleic acid alkyl chain, the triacylglycerols with oleic acid in their chain has lower melting point as the van der waal's force of attraction between molecules of triacylglycerol weakens because of the kink and bent produced by the unsaturation.

But in case of palmitic acid, it can align properly in straight chain to ensure proper stacking and stronger van der waals force between molecules. Hence,, more number of palmitic acid chains will result in higher melting point.

Now, the order of the melting point in increasing order can be written as

Note that the melting point of PPO and POP will be pretty much similar because of the same constituent. Similar trend can be observed for OOP and OPO.