Re: Is the molecule chitin polar or non-polar?

Date: Thu Nov 20 08:09:09 2008
Posted By: Rafael Garcia, Faculty, Fats, oils and Animal Co-Products, USDA-ARS
Area of science: Biochemistry
ID: 1227148764.Bc

Message:

Polarity is like money, you can have none, a little, or a lot; so the question really is 'how polar is chitin?'.

You can get an estimate of a molecule's polarity by looking at its structure. C-H and C-C bonds will not contribute much or any polarity to a molecule.

Structure of Hexane

Look up the structure of hexane on Wikipedia. It is made up of nothing but C-C and C-H bonds and the hexane molecule has very low polarity.

Structure of Sorbitol

O-H and N-H bonds contribute a lot of polarity to a molecule. Look up the structure of sorbitol; it is loaded with O-H bonds and sorbitol is a very polar molecule.

Now look up the structure of chitin.

Structure of Chitin

I has some O-H and N-H bonds, but it is not as loaded with them as sorbitol is, so just based on looking at the structure you can say it has an intermediate polarity.

You can learn more about how molecular structure effects polarity to get a better estimate of polarity than that, but a better way to determine the polarity is to actually do an experiment to measure it. The most efficient way to determine the polarity of a molecule it to look it up, because someone has probably done this experiment before and reported the results.

Good luck with your studies! -Rafael

**Please note that the author is answering on his own behalf and the above should not be considered a statement from his employer.

Current Queue | Current Queue for Biochemistry | Biochemistry archives

Try the links in the MadSci Library for more information on Biochemistry.