If I only have the name of this transitional coordination compound, bis(enthylenediamine)dinitroiron (III) sulphate how do you find the 2 outside the square bracket of this same thing but in formula form? [Fe (en)2 (NO2)2]2SO4 thanks.

Answer 1

maybe this would help?
http://www.coursehero.com/file/p6s4k6su/Bis-ethylenediamine-More-Nomenclature-Feen-2-NO-2-2-2-SO-4-Bisethylenediamine/