Question

Which of the followining is NOT true of unsaturated fats?

  

oleic acid is an example

   

more liquid at room temperature than saturated fatty acids

   

contain no double bonds

   

contain at least one double bond

   

most naturally occuring are "bent" (cis)

Answer 1

The answer is unsaturated fats contain no double bonds.Unsaturated fats are fat or fatty acids that contain atleast one double bond in the chain.If one double bond it is called Monounsaturated fat.It more than one double bond it is called polyunsaturated fat.Saturated fat doesn't contain any double bonds.oleic acid is a mono unsaturated fat.Unsaturated fats are more liquid at room temperature .Saturated fatty acids are more solid at room temperature.Saturated fatty acids have more melting point than corresponding unsaturated fatty acids.Unsaturated fats have double or triple bonds between the carbon atoms that make it weaker and and appear more fluid in nature.Most of the naturally occurring fatty acids have bent or cis conformation.In cis conformation,hydrogen atoms around the double bond are present in the same plane.This cis form causes a bend in the structure of fatty acid.THis bend structure prevents the molecules from tight packing and make it appear more fluid in nature.

H Cis form . H OH a Cis conformation of monounsaturated fally and CH