Question

What is the IUPAC name of [Pt(NH₃)₂Cl(NO₂)]?

• A. Diamminechloridonitrito-N-platinum(II)
• B. Diamminechloridenitrito-N-platinum(III)
• C. Diamminechloridonitrito-O-platinum(II)
• D. Diammonia chloridonitrito-N-platinum(II)

Answer 1

The Correct Option is A

To determine the IUPAC name for the complex [Pt(NH₃)₂Cl(NO₂)], we need to follow the rules for naming coordination compounds:

• Identify the ligands and their order: The ligands are listed alphabetically in the compound's name, ignoring any prefixes. Here, we have two ligands: Ammine (NH₃) and Chlorido (Cl) along with Nitrito, which is a bidentate ligand and specifically bound via the nitrogen atom in this context, hence Nitrito-N.
• Determine the oxidation state of the metal: Platinum (Pt) is the central metal in this complex. The ammonia (NH₃) ligands are neutral, chlorido (Cl) is -1, and nitrito-N (NO₂) is -1. The overall charge for the molecule is neutral, thus: Ptn+(2×0)+(1×-1)+(1×-1)=0, giving us n = +2 for platinum. Hence, it is platinum(II).
• Name the complex: Combine the ligand names with the metal in the following manner: "Diamminechloridonitrito-N-platinum(II)". Note the use of "Diammine" for two amine groups, "chlorido" for Cl, and "nitrito-N" indicating the nitrogen atom as the donor atom.

Thus, the correct IUPAC name is: Diamminechloridonitrito-N-platinum(II).

Answer 2

[Pt(NH₃)₂Cl(NO₂)] is the coordination compound.

• NH₃ is the ammine ligand, Cl is the chlorido ligand, and NO₂ is the nitrito ligand, which is bound through the nitrogen (N), not oxygen (O).
• Platinum (Pt) has an oxidation state of +2.
• The name follows the order of ligands: Ammine (NH₃), Chlorido (Cl), and Nitrito-N (NO₂ bound through nitrogen).

Thus, the correct IUPAC name is Diamminechloridonitrito-N-platinum(II).