Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
COMEDK20269 May 2026Morning ShiftChemistryGeneral Organic ChemistryActual

Lassaigne's test for the detection of nitrogen fails in

Options

  1. ANH ₂ CONH ₂
  2. BNH ₂ - NH ₂ HCl
  3. CNH ₂ CONHNH ₂ HCl
  4. DC ₆ H ₅ NHNH ₂ HCl

Correct answer

B. NH ₂ - NH ₂ HCl

Step-by-step solution

Lassaigne's test for the detection of nitrogen involves the fusion of the organic compound with sodium metal to form sodium cyanide ( NaCN ). For the formation of cyanide ion ( CN ⁻ ), both carbon and nitrogen must be present in the organic compound. Hydrazine hydrochloride ( NH ₂ -NH ₂ HCl ) does not contain carbon. Therefore, it cannot form sodium cyanide upon fusion with sodium metal, and Lassaigne's test for nitrogen fails. The other compounds ( NH ₂ CONH ₂ , NH ₂ CONHNH ₂ HCl , and C ₆ H ₅ NHNH ₂ HCl ) contain

Practice General Organic Chemistry on Quantrex Academy →

More from General Organic Chemistry

Which of the following is an INCORRECT statement? 2026Identify the aromatic compounds among the given set based on Huckel's rule: 2026Among the given resonating structures of molecules negative mesomeric effect is represented by: 2026Identify the correct structure of o-ethyl anisole. 2026Match the mixtures listed in Column I with the correct method used for their separation. Column I Column II A. Glycerol from spent Lye P. Steam distillation B. Mixture of Benzoic a 2026Which one of the following is not the correct IUPAC name of the compound? 2026Consider the sets I, II and III. Identify the set(s) which is (are) correctly matched. I. Staggered ethane > eclipsed ethane ......... torsional strain. II. 2, 2-Dimethylbutane > 2 2025IUPAC names of the given compounds (I) and (II) are respectively 2025 Full General Organic Chemistry list All COMEDK PYQs