Physical properties of lipids

Hydrophilic character of carboxylic acid group and hydrophobic character of hydrocarbon chain.
Low water solubility as the hydrocarbon chain character is greater than the carboxylic carbon character.
Solubility decreases when there is a longer hydrocarbon chain.
Lipids with a single carbon-carbon bonds (saturated) have a minimum melting temperature around 30 and increases with the length of the chain.
Saturated fatty acids are commonly present in solid state at room temperature.
Melting point of lipids that have one or more double carbon-carbon bonds (monounsaturated and polyunsaturated) have a lower melting point.
Monounsaturated and polyunsaturated fatty acids are commonly present in liquid state at room temperature.
Unsaturated fatty acids have weaker London Dispersion forces.
Lipids are polymorphs, they have different forms when they packed themselves or form crystalline structures.

Bibliography:

Biomolecules