Q.61 Chemistry ⭐ 360° Option Elimination Active

Vault ↗

NEET 2023 Chemistry Question 61 Solution

Topic: Coordination Compounds · Official NTA Booklet Code G5

Question

Homoleptic complex from the following complexes is:

✓

Verified Against NTA Final Answer Key

Option (2) : Potassium trioxalatoaluminate (III)

📚 Coordination Compounds Easy

📋 Given Parameters & Problem Setup

Target classification Homoleptic complex

Definition Central metal atom/ion bound to only ONE type of donor group/ligand

⚡

The 30-Second Exam Hall Shortcut: ⚡ Prefix & Ligand Variety Scan: Homo = ONE Ligand Type

⏱️ Save ~30 seconds

Potassium trioxalatoaluminate (III) is K₃[Al(C₂O₄)₃], containing ONLY oxalate ligands! All other options contain two or three different ligand types (heteroleptic). Option (2) in 5 seconds!

1 Homoleptic complex: A coordination entity where the metal is bound to only ONE kind of ligand.

2 Heteroleptic complex: A coordination entity where the metal is bound to more than one kind of ligand.

3 Option (1): Triamminetriaquachromium (III) chloride contains NH₃ AND H₂O (two ligand kinds ⟹ Heteroleptic).

4 Option (2): Potassium trioxalatoaluminate (III) contains ONLY oxalate (ox²⁻) ligands ⟹ HOMOLEPTIC.

5 Option (3): Diamminechloridonitrito-N-platinum (II) contains NH₃, Cl⁻, and NO₂⁻ (three ligand kinds ⟹ Heteroleptic).

6 Option (4): Pentaamminecarbonatocobalt (III) chloride contains NH₃ AND CO₃²⁻ (two ligand kinds ⟹ Heteroleptic).

7 Select Option (2) directly!

🛡️

Why You Can 100% Trust This Shortcut: Coordination Chemistry · IUPAC Terminology (Complexes in which a metal is bound to only one kind of donor groups are homoleptic, e.g., [Al(C₂O₄)₃]³⁻).

📐

Step-by-Step Rigorous Workflow & Mathematical Proof

Step 1

Definition of Homoleptic Coordination Entities

According to IUPAC coordination chemistry conventions, complexes are classified based on the diversity of their coordinating donor ligands: (i) Homoleptic complexes: complexes in which the central metal atom or ion is coordinated to only ONE type of ligand species; (ii) Heteroleptic complexes: complexes in which the metal ion is coordinated to two or more chemically distinct types of ligands.

\text{Homoleptic: } [\text{M}(\text{L})_n]^{m\pm}, \qquad \text{Heteroleptic: } [\text{M}(\text{L}_1)_a(\text{L}_2)_b]^{m\pm}

Step 2

Chemical Formula of Option 2

Potassium trioxalatoaluminate (III) has the chemical formula K₃[Al(C₂O₄)₃]. In this complex, the central aluminum(III) ion is coordinated exclusively to three bidentate oxalate ligands (C₂O₄²⁻):

\text{K}_3[\text{Al}(\text{C}_2\text{O}_4)_3] \implies \text{Coordination sphere contains only oxalate ligands } (\text{Homoleptic})

Step 3

Formulas and Analysis of Heteroleptic Distractors

Writing the coordination formulas for the remaining choices reveals multiple distinct ligand types:

\begin{aligned} \text{Option 1: } &[\text{Cr}(\text{NH}_3)_3(\text{H}_2\text{O})_3]\text{Cl}_3 \quad (\text{Ligands: } \text{NH}_3, \text{H}_2\text{O} \implies \text{Heteroleptic}) \\[4pt] \text{Option 3: } &[\text{Pt}(\text{NH}_3)_2\text{Cl}(\text{NO}_2)] \quad (\text{Ligands: } \text{NH}_3, \text{Cl}^-, \text{NO}_2^- \implies \text{Heteroleptic}) \\[4pt] \text{Option 4: } &[\text{Co}(\text{NH}_3)_5(\text{CO}_3)]\text{Cl} \quad (\text{Ligands: } \text{NH}_3, \text{CO}_3^{2-} \implies \text{Heteroleptic}) \end{aligned}

⭐

360° Option Elimination Engine Key Feature

Diagnose every choice: Know exactly why the right option works and why distractors fail.

4-Option Deep Scan

1 (1)

✗ Incorrect

Verdict & Scientific Reason:

Heteroleptic: contains both ammine (NH₃) and aqua (H₂O) ligands.

⚠️

Student Fallacy (Why candidates pick this trap): Candidate saw identical stoichiometric counts (3 and 3) and guessed homoleptic.

2 (2)

✓ 100% Correct

Verdict & Scientific Reason:

Accurate homoleptic complex: contains exclusively oxalate ligands [Al(C₂O₄)₃]³⁻.

💡

Why this is airtight: None. Candidate correctly verified single ligand type.

3 (3)

✗ Incorrect

Verdict & Scientific Reason:

Heteroleptic: contains three distinct ligand types (ammine, chlorido, nitrito-N).

⚠️

Student Fallacy (Why candidates pick this trap): Candidate overlooked the presence of multiple ligands.

4 (4)

✗ Incorrect

Verdict & Scientific Reason:

Heteroleptic: contains ammine and carbonato ligands.

⚠️

Student Fallacy (Why candidates pick this trap): Candidate saw pentaammine (5 ammines) and ignored the carbonato ligand.

⚠️

NTA Trap Alert: Confusing Counter Ions with Coordination Ligands

Potassium (K⁺) in K₃[Al(C₂O₄)₃] is an ion outside the coordination bracket. Only the species INSIDE the coordination square brackets define homoleptic vs heteroleptic character.

🛡️ How to avoid the -1 mark: Focus strictly inside the brackets: If there is only ONE type of ligand inside [ ], it is homoleptic.

📖

Core NEET Syllabus Standard

National Eligibility cum Entrance Test (NEET UG) · Coordination Compounds Standard Benchmark

Core Scientific Principle Tested:

"Homoleptic complexes have central metal bound to only one kind of donor groups; heteroleptic complexes have more than one kind."

Syllabus Focus: Definitions of Some Important Terms Pertaining to Coordination Compounds

Preserved in Rationalized Curriculum Syllabus & Academic Standards ↗

Ready to attempt under real exam pressure?

Test your speed and accuracy in the authentic 200-minute timed NTA simulator.

Launch NEET 2023 CBT Test →

← Previous (Q.60) All Chemistry Questions Grid Next (Q.62) →

Spotted a mistake in this solution? Report an error ([email protected])

⚖️ Legal & Fair Dealing Notice: Sourced from publicly released NEET 2023 question papers and NEET answer keys for private study, research, and non-commercial educational practice under Fair Dealing (Section 52(1)(a) of the Indian Copyright Act, 1957). Not affiliated with or endorsed by NTA or NMC.

NEET 2023 Chemistry Question 61 Solution

Question

The 30-Second Exam Hall Shortcut: ⚡ Prefix & Ligand Variety Scan: Homo = ONE Ligand Type

Step-by-Step Rigorous Workflow & Mathematical Proof

Definition of Homoleptic Coordination Entities

Chemical Formula of Option 2

Formulas and Analysis of Heteroleptic Distractors

360° Option Elimination Engine Key Feature

NTA Trap Alert: Confusing Counter Ions with Coordination Ligands

Core NEET Syllabus Standard

Ready to attempt under real exam pressure?

🔗 Related Questions — Coordination Compounds

Coordination Isomerism & IUPAC Nomenclature of Bimetallic Complexes

Ionic Dissociation & Ion Ratio in Potash Alum

Spectrochemical Series & Ligand Field Strength Ordering

Spin-Only Magnetic Moments of Octahedral 3d Complexes

Solve 4 NEET Questions a Day — One per Subject