Free radicals formd by homolytic clevage.which means if a covalent bond breaks in such a way that each atom takes away one electron of the shared pair it is called homolytic clevage..
FREE RADICAL HAVE SP2 hybridisation , but it varies from types of free radical , so, metion the question properly .
the stability of a carbocationdecreases as you go from sp3 to sp2 to sp,
but they are generally sp3 .
the hybridisation of carbanion is sp3 and the structure is pyramidal .
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