Covalent - equal sharing of generally one pair of electrons (e.g. H2 hydrogen molecule)Polar covalent- ubequal sharing - the more electronegative element "attracts " the electrons in the bond towards it causing the formation of a small negative charge (and a small compensating positive charge on the less electronegative atom) example HCl, hydrogen chloride moleculeA hydrogen bond is a weak electrostatic bond invoving a hydrogen atom covakently bonded to one atom attracted to a very electrnegative atom. (Example is water, H2O)