[Co(H2NCH2CH2NH2)3]2(SO4)3 is named as:
tris(ethane-1,2–diamine)cobalt(III) sulphate
Explanation: The sulphate is the counter anion in this molecule Since it takes 3 sulphates to bond with two complex cations, the
charge on each complex cation must be +3 Further, ethane-1,2–
diamine is a neutral molecule, so the oxidation number of cobalt
in the complex ion must be +3 Remember that you never have to
indicate the number of cations and anions in the name of an
ionic compound