NEET UG · Chemistry · Coordination Compounds

Crystal Field Theory: NEET previous year questions

10 questions in ten years of NEET, in 8 of 10 papers. Pattern: Every year. Here is how it is asked and which ideas come back.

Asked in 10 years: 10; about 1.0 per paper
Years asked: 8/10; last asked 2026
Chance of a question next paper: 64%; historical rate, how we compute it
Weighted estimate: 1.1; model; history: 1.0 a paper on average, typically 0–2

Key findings

01
Asked in 8 of 10 papers, 10 questions in all: #73 of 204 topics by ten-year total. It comes back every 1.3 years on average.
02
44% of its questions since 2018 tested an idea never asked before; none repeated an idea from the year before.
03
The most repeated idea is Spectrochemical Series Usage, asked 3 times (2020, 2022, 2026), usually as “order/ranking of ligand field strength”.
04
NEET has asked 5 of the 88 ideas in this topic; 79 have never been asked, directly or indirectly.
05
Mostly asked as one-line MCQ (80%); 10% easy, 0% hard, and up from 0.8 to 1.3 questions a paper since 2024.

Questions per year

Up to 2023: 0.8; per paper
Since 2024: 1.3; +0.5
Usual gap: 1.3 yrs; between papers asking it
Swing: ±0.6; questions, year to year

How it is asked

Difficulty, format and skill

Across all 10 questions on Crystal Field Theory since 2017.

Difficulty

QUESTIONS

Easy1 · 10%
Medium9 · 90%
Hard0 · 0%

Format

One-line MCQ · 8 Q80%
Other · 1 Q10%
Match the lists · 1 Q10%

Skill tested

Multi-step · 4 Q40%
Recall · 3 Q30%
Application · 2 Q20%
Concept · 1 Q10%

Repeats

New idea, or one asked before?

Each column is a paper. Blue questions tested an idea NEET had not asked before; navy ones went back to an idea from an earlier paper. 2017 is the first paper, so everything in it counts as new.

’17’18’19’20’21’22’23’24’25’26

Idea asked for the first time
Idea asked in an earlier paper

Coverage of the topic

NEET has asked 5 of the 88 ideas in this topic. 79 have never been asked yet.

Asked directly5 · 6%
Touched inside another question4 · 5%
Never asked79 · 90%

Ideas come from Lumi’s syllabus map of NCERT. A never-asked idea is not a safe skip: most new questions come from exactly these.

Drill down

Idea, year, question

Every idea NEET tested in this topic, with its ten papers. Open one to read the questions.

ideaAskedShareYears’17’18’19’20’21’22’23’24’25’26

Repeated3 · 30%30%3/10
- 2026 · Q58
  According to crystal field theory, the correct order of ligands with respect to their decreasing order of field strength is
  easyOne-line MCQ
- 2022 · Q98
  The order of energy absorbed which is responsible for the color of complexes (A) $\mathrm{[Ni(H_2O)_2(en)_2]^{2+}}$ (B)…
  mediumOne-line MCQ
- 2020 · Q116
  Which of the following is the correct order of increasing field strength of ligands to form coordination compounds ?
  mediumOne-line MCQNew idea
Repeated2 · 20%20%2/10
Repeated2 · 20%20%2/10
Repeated2 · 20%20%2/10
1 · 10%10%1/10

Squares are the ten papers, 2017 to 2026; darker means more questions. Share is of the level above.

Ideas

Every idea inside this topic

5 different ideas were tested; 4 came more than once. Spectrochemical Series Usage is the foundation for 65 other ideas in the syllabus.

Spectrochemical Series Usage3×
order/ranking of ligand field strength
One-line MCQ · 11% next · foundation for 65
Spin-Only Magnetic Moment via CFT2×
match list on magnetic moments of complexes
Match the lists · 6% next · foundation for 2
Absorbed Wavelength and Splitting Energy2×
order/ranking of property
One-line MCQ · 6% next
Nickel Complex Geometry Trio2×
geometry and magnetism of complex
Other · 6% next
Hexacyanoferrate vs Hexafluoroferrate Comparison1×
electronic configuration of complex ion
One-line MCQ · 4% next

Idea	Times	Format	Chance next	Foundation for
Spectrochemical Series Usageorder/ranking of ligand field strength	3	One-line MCQRecall	11%	65 ideas
Spin-Only Magnetic Moment via CFTmatch list on magnetic moments of complexes	2	Match the listsMulti-step	6%	2 ideas
Absorbed Wavelength and Splitting Energyorder/ranking of property	2	One-line MCQApplication	6%	–
Nickel Complex Geometry Triogeometry and magnetism of complex	2	OtherMulti-step	6%	–
Hexacyanoferrate vs Hexafluoroferrate Comparisonelectronic configuration of complex ion	1	One-line MCQApplication	4%	–

Chance next is the historical rate at which an idea with this record came back in the following paper. It is low for every idea, which is why learning the topic beats memorising past questions. All repeated ideas

Every question

Crystal Field Theory questions, year by year

The opening words of each question as it appeared in the official paper, with the idea it tested.

NEET 20262 questions

Q58
According to crystal field theory, the correct order of ligands with respect to their decreasing order of field strength is
Idea: Spectrochemical Series Usage
EasyOne-line MCQ
Q66
Among the species given below, the spin-only magnetic moment is highest for (Given : Atomic number of Ti = 22, Mn = 25, Fe = 26 and Co = 27)
Idea: Spin-Only Magnetic Moment via CFT
MediumOne-line MCQ

NEET 20252 questions

Q51
Which of the following are paramagnetic? A. $[NiCl_4]^{2-}$ B. $Ni(CO)_4$ C. $[Ni(CN)_4]^{2-}$ D. $[Ni(H_2O)_6]^{2+}$ E. $Ni(PPh_3)_4$ …
Idea: Nickel Complex Geometry Trio
MediumOther
Q57
The correct order of the wavelength of light absorbed by the following complexes is, A. $[Co(NH_3)_6]^{3+}$ B. $[Co(CN)_6]^{3-}$ C.…
Idea: Absorbed Wavelength and Splitting Energy
MediumOne-line MCQ

NEET 20221 question

Q98
The order of energy absorbed which is responsible for the color of complexes (A) $\mathrm{[Ni(H_2O)_2(en)_2]^{2+}}$ (B)…
Idea: Spectrochemical Series Usage
MediumOne-line MCQ

NEET 20211 question

Q94
Match List - I with List - II. List - I | List - II (a) $\mathrm{[Fe(CN)_6]^{3-}}$ | (i) 5.92 BM (b) $\mathrm{[Fe(H_2O)_6]^{3+}}$ | (ii) 0…
Idea: Spin-Only Magnetic Moment via CFT
New ideaMediumMatch the lists

NEET 20201 question

Q116
Which of the following is the correct order of increasing field strength of ligands to form coordination compounds ?
Idea: Spectrochemical Series Usage
New ideaMediumOne-line MCQ

NEET 20191 question

Q75
What is the correct electronic configuration of the central atom in $K_4[Fe(CN)_6]$ based on crystal field theory ?
Idea: Hexacyanoferrate vs Hexafluoroferrate Comparison
New ideaMediumOne-line MCQ

NEET 20181 question

Q73
The geometry and magnetic behaviour of the complex $\mathrm{[Ni(CO)_4]}$ are
Idea: Nickel Complex Geometry Trio
New ideaMediumOne-line MCQ

NEET 20171 question

Q73
Correct increasing order for the wavelengths of absorption in the visible region for the complexes of $\mathrm{Co^{3+}}$ is :
Idea: Absorbed Wavelength and Splitting Energy
MediumOne-line MCQ

Questions from the official NEET UG papers published by NTA (CBSE before 2019). Topic and idea tags, counts and notes are Lumi’s.