As per IUPAC nomenclature, the name of the complex $[\mathrm{Co}(\mathrm{H}_{2} \mathrm{O})_{4}(\mathrm{NH}_{3})_{2}] \mathrm{Cl}_{3}$ is

(D) Diamminetetraaquacobalt (III) chloride

(A) Tetraaquadiaminecobalt (III) chloride

(B) Tetraaquadiamminecobalt (III) chloride

(C) Diaminetetraaquacobalt (III) chloride

JEE Advanced · 2012 · 08 Apr 2012 · Paper 1 · Coordination Compounds

As per IUPAC nomenclature, the name of the complex

[Co (H_{2} O)_{4} (NH_{3})_{2}] Cl_{3}

Answer: (D)

According to IUPAC nomenclature for coordination compounds: (1) Ligands are named in alphabetical order before the metal. (2)

NH_{3}

as a ligand is called "ammine" (with double 'm'). (3)

H_{2} O

as a ligand is called "aqua". (4) 'D' comes before 'T' alphabetically. (5) The oxidation state of Co is +3 (since the complex has +3 charge and

Cl_{3}

provides -3). Therefore, the correct name is Diamminetetraaquacobalt (III) chloride.

JEE Advanced · 2012 · 08 Apr 2012 · Paper 1 · Single correct option