In acid media, the corrosion inhibition offered by ethanol amines, benzoic acids, acetylinic alcohols for iron and nickel was investigated These molecules adsorbed on the metal surface and offered inhibition. A correlation between inhibition and electronic configuration of the molecules was attempted. In benzoic acids, the anchoring group is the benzene ring and the electron delocalisation in the aromatic ring played a crucial role in the surface chelate formation. In the case of amines, the inhibition takes place due to adsorption via lone pair of electrons on the nitrogen atoms. Acetylinic alcohols offered inhibition by accepting electrons from the vacant: ＇d＇ orbitals of the transition metals. On prolonged exposure in acid medium they form thick polymeric film on the metals thus offering inter-phase inhibition.