
Which of the following complexes is diamagnetic? [RPMT 1997]
(A) $[Ni{{(CO)}_{4}}]$
(B) ${{[NiC{{l}_{4}}]}^{2-}}$
(C) ${{[NiB{{r}_{4}}]}^{2-}}$
(D) $[NiC{{l}_{2}}].4{{H}_{2}}O$
Answer
161.1k+ views
Hint: Firstly, we have to determine the electronic configuration of metal ions present in the complexes. Then, according to the strength of the ligands attached to the metal, the pairing of the electrons occurs. If in a complex, all the electrons are paired up, then the complex is diamagnetic.
Complete answer:The electronic configurations of the metal ions present in the solution are as shown:
(A) $[Ni{{(CO)}_{4}}]$
$N{{i}^{{}}}$- $[Ar]3{{d}^{8}}$
$CO$ is a strong ligand. It induces a pairing of electrons as four $CO$ ligands approach the nickel metal. So, it is diamagnetic.
(B) ${{[NiC{{l}_{4}}]}^{2-}}$
$N{{i}^{2+}}$ - $[Ar]3{{d}^{6}}$
$C{{l}^{-}}$ is a weak ligand. It does not induce the pairing of electrons as ligands approach the nickel metal. So, it is paramagnetic.
(C) ${{[NiB{{r}_{4}}]}^{2-}}$
$N{{i}^{2+}}$ - $[Ar]3{{d}^{6}}$
$B{{r}^{-}}$ is a weak ligand. It does not induce the pairing of electrons as ligands approach the nickel metal. So, it is paramagnetic.
(D) $[NiC{{l}_{2}}].4{{H}_{2}}O$
$N{{i}^{2+}}$ - $[Ar]3{{d}^{6}}$
$C{{l}^{-}}$ is a weak ligand. It does not induce the pairing of electrons as ligands approach the nickel metal. So, it is paramagnetic.
Hence, among the following complexes, $[Ni{{(CO)}_{4}}]$ is diamagnetic.
Correct Option: (A) $[Ni{{(CO)}_{4}}]$
Note: Complexes of the coordination compounds exhibit magnetic characteristics. The quantity of unpaired electrons in a molecule determines its magnetic properties, and the electronic spin produces magnetism. There are primarily three forms of magnetism exhibited by the complexes: ferromagnetism, paramagnetism, and diamagnetism. If any unpaired electrons are present in the complex, it is said to be paramagnetic.
Complete answer:The electronic configurations of the metal ions present in the solution are as shown:
(A) $[Ni{{(CO)}_{4}}]$
$N{{i}^{{}}}$- $[Ar]3{{d}^{8}}$
$CO$ is a strong ligand. It induces a pairing of electrons as four $CO$ ligands approach the nickel metal. So, it is diamagnetic.
(B) ${{[NiC{{l}_{4}}]}^{2-}}$
$N{{i}^{2+}}$ - $[Ar]3{{d}^{6}}$
$C{{l}^{-}}$ is a weak ligand. It does not induce the pairing of electrons as ligands approach the nickel metal. So, it is paramagnetic.
(C) ${{[NiB{{r}_{4}}]}^{2-}}$
$N{{i}^{2+}}$ - $[Ar]3{{d}^{6}}$
$B{{r}^{-}}$ is a weak ligand. It does not induce the pairing of electrons as ligands approach the nickel metal. So, it is paramagnetic.
(D) $[NiC{{l}_{2}}].4{{H}_{2}}O$
$N{{i}^{2+}}$ - $[Ar]3{{d}^{6}}$
$C{{l}^{-}}$ is a weak ligand. It does not induce the pairing of electrons as ligands approach the nickel metal. So, it is paramagnetic.
Hence, among the following complexes, $[Ni{{(CO)}_{4}}]$ is diamagnetic.
Correct Option: (A) $[Ni{{(CO)}_{4}}]$
Note: Complexes of the coordination compounds exhibit magnetic characteristics. The quantity of unpaired electrons in a molecule determines its magnetic properties, and the electronic spin produces magnetism. There are primarily three forms of magnetism exhibited by the complexes: ferromagnetism, paramagnetism, and diamagnetism. If any unpaired electrons are present in the complex, it is said to be paramagnetic.
Recently Updated Pages
JEE Main 2021 July 25 Shift 1 Question Paper with Answer Key

JEE Main 2021 July 22 Shift 2 Question Paper with Answer Key

JEE Main Mock Test Series Class 12 Chemistry for FREE

Classification of Drugs Based on Pharmacological Effect, Drug Action

JEE Electricity and Magnetism Important Concepts and Tips for Exam Preparation

JEE Energetics Important Concepts and Tips for Exam Preparation

Trending doubts
JEE Main 2025 Session 2: Application Form (Out), Exam Dates (Released), Eligibility, & More

JEE Main 2025: Derivation of Equation of Trajectory in Physics

Electric Field Due to Uniformly Charged Ring for JEE Main 2025 - Formula and Derivation

Displacement-Time Graph and Velocity-Time Graph for JEE

JEE Main 2026 Syllabus PDF - Download Paper 1 and 2 Syllabus by NTA

JEE Main Eligibility Criteria 2025

Other Pages
JEE Advanced Marks vs Ranks 2025: Understanding Category-wise Qualifying Marks and Previous Year Cut-offs

NCERT Solutions for Class 12 Chemistry Chapter 1 Solutions

JEE Advanced 2025: Dates, Registration, Syllabus, Eligibility Criteria and More

NCERT Solutions for Class 12 Chemistry Chapter 2 Electrochemistry

NCERT Solutions for Class 12 Chemistry Chapter 6 Haloalkanes and Haloarenes

Solutions Class 12 Notes: CBSE Chemistry Chapter 1
