eng Science and Education Publishing World Journal of Chemical Education 2375-1657 2022-01-03 10 1 20 22 10.12691/wjce-10-1-3 WJCE20221013 article R. Sanjeev 1 D. A. Padmavathi 2 V. Jagannadham jagannadham1950@yahoo.com 2 Department of Chemistry, Geethanjali College of Engineering and Technology, Cheeryal-501301, Telangana, India Department of Chemistry, Osmania University, Hyderabad-500007, India In chemistry literature it is so far achieved to distinguish o,p-directing groups from m-directing groups purely on the basis of only relative yields of ortho, para and meta electrophilic substituted products in the benzene ring and it is also based on their ability to disturb the pi-electron density at the carbons. It is for the first time in chemistry literature using dipole moment data a linear free energy relationship (LFER), Hammett equation is used to distinguish o,p-directing groups from m-directing groups. This could be achieved by constructing Hammett plots with dipole moments versus Hammett para substituent constants for electron donating groups and Hammett meta substituent constants for electron withdrawing groups. Good straight lines are obtained with correlation coefficients close to 0.9 with certainly an unmistakable trend. http://pubs.sciepub.com/wjce/10/1/3/wjce-10-1-3.pdf hammett equation dipole moments o p-Directing groups m-Directing groups