SYMBOLS AND ABBREVIATIONS text.Do not expect all of these to make sense to the textbook by W you now.I your study of organic chemistry) BONDS a single bond a double bond a triple bond a bond in three dimensions.coming out of the paper toward the reader a bond in three dimensions.going behind the paper away from the reader a stretched bond,in the process of forming or breaking ARROWS in a reaction,shows direction from reactants to products signifies equilibrium(not to be confused with resonance) signifies resonance(not to be confused with equilibrium) shows direction of electron movement: the arrowhe with one the arrowhead with two barb 十 shows polarity of a bond or molecule,the arrowhead signifying the more negative end of the dipole SUBSTITUENT GROUPS Me a methyl group,CH 号 an ethyl group,CH2CH3 Pr a propyl group,a three-carbon group (two possible arrangements) a butyl group,a four-carbon group(four possible arrangements) R the general abbreviation for an alkyl group(or any substituent group bonded at carbon) Ph a phenyl group,the name of a benzene ring as a substituent.represented Ar the general abbreviation for an aromatic group continued on next page vii Copyright013 Pearson Education,Ine