(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: