Question

When a co-ordination compound CrCl₃.6H₂O is mixed with AgNO₃, 2 moles of AgCl are precipitated per mole of the compound. Write

(i) Structural formula of the complex.

(ii) IUPAC name of the complex.

Answer 1

As two moles of AgCl are obtained; therefore, the structural formula would contain  two Cl⁻ ions satisfying the primary valencies, while five H₂O molecules and one Cl⁻ion are present inside the coordination sphere, making the coordination number 6. One H₂O molecule will be present as the molecule of hydration.

Structural formula: [CrCl(H₂O)₅]Cl₂.H₂O

IUPAC name of the compound: Pentaaquachloridochromium(III) chloride