Indicating Steps in Mechanisms Curved arrows indicate breaking and forming of bonds ■Arrowheads with a“half'head(“fish- hook")indicate one electron movement (called 'radical processes') A radical is a neutral chemical species that contains an odd number of electrons and thus has a single, unpaired electron in one of its orbitals Arrowheads with a complete head indicate two electrons movement (called 'polar processes')Indicating Steps in Mechanisms „ Curved arrows indicate breaking and forming of bonds „ Arrowheads with a “half” head (“fish￾hook”) indicate one electron movement (called ‘radical processes’) A radical is a neutral chemical species that contains an odd number of electrons and thus has a single, unpaired electron in one of its orbitals „ Arrowheads with a complete head indicate two electrons movement (called ‘polar processes’)