Fatty acids : Fatty acids are organic acids with a long hydrocarbon chain ending in carboxyl group (-СООН).
Characteristics of fatty acids are:
(i) Has a long chain of carbon atoms.
(ii) Is insoluble in water.
(iii) Is soluble in organic solvents.
(iv) Must leave an oily spot on a piece of paper.
(i) Saturated fatty acids : They do not have any double bond in between carbon atoms of molecular chain. Examples are:
Palmitic acid - CH3(CH2)14СООН
Stearic acid – CH3(CH2)16СООН
(ii) Unsaturated fatty acids: They have one or more double bonds in between carbon atoms of molecular chain. Unsaturated fatty acids have lower melting points as compared to saturated fatty acids. Examples are:
Oleic acid – CH3 (CH2)7CH = CH(CH2)7 COOH
Linoleic acid – CH3(CH2)4CH = (CHCH2)2 (CH2)6 COOH
