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Friday, 9 October

NEET UG 2025 · Chemistry · Question 90

NEET 2025 Chemistry, question 90

Question 90 of the NEET 2025 paper (code 45) is a Chemistry question from Organic Chemistry - Some Basic Principles and Techniques. Its idea, Lassaigne's Test for N and Halogens, was asked twice, in 2023 and 2025, across NEET 2017–2026. The NTA final answer key gives option 4.

Updated 2026-10-08

Q90 · Chemistry

Which one of the following reactions does NOT belong to “Lassaigne's test”?

  1. 1Na+C+N→ΔNaCNNa + C + N \xrightarrow{\Delta} NaCN
  2. 22Na+S→ΔNa2S2Na + S \xrightarrow{\Delta} Na_2S
  3. 3Na+X→ΔNaXNa + X \xrightarrow{\Delta} NaX
  4. 42CuO+C→Δ2Cu+CO22CuO + C \xrightarrow{\Delta} 2Cu + CO_2Official answer

Official answer: option 4 · NTA final answer key

Same idea

Lassaigne's Test for N and Halogens, in other papers

NEET asked this idea twice, in 2023 and 2025. The other question below.

  • 2023 Q54In Lassaigne's extract of an organic compound, both nitrogen and sulphur are present, which gives blood red colour with Fe3+^{3+} due to…One-line MCQ · Medium

Lassaigne's Test for N and Halogens: every question and how it was framed

The chapter

Organic Chemistry - Some Basic Principles and Techniques in ten years of NEET

22 questions from 2017–2026, asked in 10 of 10 papers, about 2.1 a paper. Purification, Analysis and Isomerism of Organic Compounds alone had 11.

Chapter analysisStudy this chapter

Organic Chemistry - Some Basic Principles and Techniques: questions per paper

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