Question

Primary and secondary valency of platinum in the complex [Pt(en)₂ Cl₂] are
a) 4,6
b) 2,6
c) 4,4
d) 6,4

Answer 1

option ''b'' is correct

Answer 2

b) 2, 6. Primary valence is its oxidation number is +2 in this case and the Cl ligands carry a -1 charge each with so Pt must be +2 balances.

Secondary valence is coordination number so ligand is bidentate with Cl is monodentate.

You could get 2(2) + 2(1) = 6, so the Pt has a coordination number of 6.