Are ClO3(-) and SO3(-2) are isostructural.if yes then why

@ shweta 
isostrctural species are those species which have same hybridisation in the central atom . 
and NO , these two are not isostrctural beacuse they have diffrent hybridisation 
in clo3- the hybridisation of cl as central atom = sp3 
in so3 2- the hybridisation of s as central atom = sp2 
so, as they have diffrent hybridisation , they are not isostrctural . 
HOPE IT CLEARS YOUR DOUBT 

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