The Student Room Group

Intermolecular forces in Aldehydes and Alkanes



Since, propane is symmetrical it is a non-polar molecule therefore it only has VDW forces. However, how do we determine that aldehydes have permanent dipole dipole forces?

Thanks
Original post by xXxiKillxXx


Since, propane is symmetrical it is a non-polar molecule therefore it only has VDW forces. However, how do we determine that aldehydes have permanent dipole dipole forces?

Thanks


Ethanal molecules have a polar C=O bond, so are polar molecules. The oxygen atom always have a high electron density, so the molecules will have London Forces and permanent dipole-dipole forces.
Reply 2
Original post by NutterFrutter
Ethanal molecules have a polar C=O bond, so are polar molecules. The oxygen atom always have a high electron density, so the molecules will have London Forces and permanent dipole-dipole forces.


Thank you, so every aldehyde is polar (since every aldehyde contains a polar C=O bond)? Also, when writing the condensed structural formula for an alkene, can you leave out the double bond as below:

Quick Reply