Question

match the following fatty acids with their transition temperature (Tm) ( 1 letter per blank) A)7 Celsius B)19 Celsius C) 65 Celsius D) 70 Celsius --------CH3(CH2)7HC=CH(CH2)7COOH ----------CH3(CH2)18COOH ------------Alpha-linoleric acid (C18:3: omega -3) ----------------------------------CH3(CH2)14COOH

Answer 1

Alpha linolenic acid has 3× C=C . Hence it will have lowest transition temperature. i.e. 7℃.

Then the acid with one C=C, CH3(CH2)7HC=CH(CH2)7COOH with transition temperature = 19℃.

-CH3(CH2)14COOH dose have less number of carbons but no C=C, hence it will have Tm = 65℃

Whereas, CH3(CH2)18COOH has largest number if Carbons and no C=C, hence it will have Tm = 70℃. The highest Tm.

As number of carbons increases Tm increases, and as number of C=C increases Tm decreases.