Answer: Triammine zinc sulfate
Explanation: In Zinc Sulfate (ZnSO4), Zinc atom exist in +2 oxidation state .
Thus 3 ammonia ligands can make a coordination complex with the Zinc Sulfate as shown below -
ZnSO4 + 3 NH3 → [Zn(NH3)] SO4
This equation can also be written in its ionic form as
Zn²⁺ + 3NH₃ = [Zn(NH₃)₃]²⁺