A complex has a molecular formula MSO₄Cl.6H₂O. Its aqueous solution gives white precipitate with barium chloride solution and no precipitate is obtained when it is treated with silver nitrate solution.

If the secondary valence of the metal is six, the correct representation of the complex is:

1. [M(H₂O)₄Cl]SO₄.2H₂O
2. [M(H₂O)₆]SO₄  
3. [M(H₂O)₅Cl]SO₄.H₂O
4. [M(H₂O)₃Cl]SO₄.3H₂O