ORGANIC CHEMISTRY Chapter 3 g a curved arrow is used to show the direction of electron flow in a reaction o The curved arrow begins with a covalent bond or unshared pair of higher electron density Department of Chemistry, Xiamen UniversityORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 3 A curved arrow is used to show the direction of electron flow in a reaction The curved arrow begins with a covalent bond or unshared pair of higher electron density