Question

While conducting an experiment on coordination compounds, Shirin observed a white precipitate when AgNO₃ solution was added to the aqueous solution of the complex [Co(NH₃)₃(en)SO₄]Cl.

How can the ionisation isomer of this complex be detected by a chemical test? Write the structure and the IUPAC name of the ionisation isomer.

Answer 1

The ionisation isomer of [Co(NH₃)₃(en)SO₄]Cl is [Co(NH₃)₃(en)Cl]SO₄.

Chemical Test to Detect Ionisation Isomer: To the ionization isomer’s aqueous solution, add the BaCl₂ solution. When free \[\ce{SO^{2-}_4}\] is present in solution, a white precipitate of BaSO₄ forms, confirming that the complex is [Co(NH₃)₃(en)Cl]SO₄.

IUPAC name of Ionisation Isomer: Triammine (ethylenediamine)chloridocobalt(III) sulphate