BP of unsaturated Fatty Acid

2014-03-23 8:08 pm

Why the boiling point of some unsaturated fatty acid such as Eicosapentaenoic acid(439.3 ℃, A unsaturated fatty acid with 20 carbon atoms and 5 double bond) and Docosahexaenoic acid(446.7 ℃, A unsaturated fatty acid with 22 carbon atoms and 6 double bond) ) have a higher boiling point than saturated acid like Lignoceric acid?

回答 (2)

Leo

2014-03-29 1:34 am

✔ 最佳答案

When molecules in the same homologous series are compared, those with higher molecular mass will have higher boiling points, as the higher members have stronger Van der Waals forces of attraction.

However, when unsaturated and saturated molecules having similar chain lengths are compared, pi-electron cloud in the unsaturated ones are more easily distorted and dipolar attraction is induced. This contributes significantly to the intermolecular forces and hence making them have higher boiling points for unsaturated molecules.

👍 0 👎 0

己式庚辛

2014-03-29 10:57 pm

Seems legit.

👍 0 👎 0