The correct stability order of the following diazonium salts is
(A) Four para-substituted benzenediazonium salts are given: plain, -OCH3, -NO2, -CN.
(B) Four para-substituted benzenediazonium salts are given: plain, -OCH3, -NO2, -CN.
(C) Four para-substituted benzenediazonium salts are given: plain, -OCH3, -NO2, -CN.
(D) Four para-substituted benzenediazonium salts are given: plain, -OCH3, -NO2, -CN.
A.A > B > C > D$\text{A} > \text{B} > \text{C} > \text{D}$
B.C > D > B > A$\text{C} > \text{D} > \text{B} > \text{A}$
C.A > C > D > B$\text{A} > \text{C} > \text{D} > \text{B}$
D.C > A > D > B$\text{C} > \text{A} > \text{D} > \text{B}$
Solution & Explanation
Core Logic
The stability of arenediazonium salts is dictated by the ability of substituents on the benzene ring to disperse the positive charge on the diazonium group (-N₂^+$\mathrm{-N_2^+}$).
Electron-donating groups (EDG) increase the stability by resonance (+M effect) and inductive (+I) effects, dispersing the positive charge.
Electron-withdrawing groups (EWG) decrease the stability by intensifying the positive charge (-M, -I effects).
Let's evaluate the given substituents at the para position:
(A) -OCH₃$\mathrm{-OCH_3}$: Strong +M effect. Highly stabilizing.
(C) Plain benzene ring: Neutral baseline.
(D) -CN$\mathrm{-CN}$: Strong -M and -I effect. Destabilizing.
(B) -NO₂$\mathrm{-NO_2}$: Very strong -M and -I effect. Most destabilizing.
Step 1: Final Conclusion
Arranging them in decreasing order of stability:
(A) -OCH₃$\mathrm{-OCH_3}$ (+M$+M$) > (C) Baseline > (D) -CN$\mathrm{-CN}$ (-M$-M$) > (B) -NO₂$\mathrm{-NO_2}$ (Stronger -M$-M$).
Thus, the correct order is A > C > D > B$\text{A} > \text{C} > \text{D} > \text{B}$.
Pattern Recognition
Stability of carbocations and diazonium ions follows: +M > +I > no effect > -I > -M$+M > +I > \text{no effect} > -I > -M$. Look directly at the para group to rank.
Chapter Mix
Class 12 Chemistry: Amines
Class 11 Chemistry: Organic Chemistry - Some Basic Principles and Techniques
Keywords:#correct stability order of diazonium salts#JEE Main 2026 Morning Q57#Amines JEE Main 2026#Stability of Diazonium Salts JEE Main 2026#Benzenediazonium#Methoxy group#Nitro group#Cyano group
More Amines Previous-Year Questions — Page 3
Q59jee_main_2026_24_january_eveningAcylation of Amines
A student has planned to prepare acetanilide from aniline using acetic anhydride. The student has started from 9.3g of aniline. However, the student has managed to obtain 11 g of dry acetanilide.
The % yield of this reaction is :-
Acylation of Amines diagram for Q59 - JEE Main 2026 Evening
Given mass of aniline (C₆H₅NH₂$C_6H_5NH_2$) = 9.3 gm
Molar mass of aniline (MW$MW$) = 93 g/mol
Moles of aniline (ntheoretical$n_{\text{theoretical}}$) = (9.3)/(93) = 0.1 moles$\frac{9.3}{93} = 0.1 \text{ moles}$
Given mass of dry acetanilide (C₆H₅NHCOCH₃$C_6H_5NHCOCH_3$) obtained = 11 gm
Molar mass of acetanilide (MW$MW$) = 135 g/mol
Moles of acetanilide obtained (nactual$n_{\text{actual}}$) = (11)/(135) 0.08148 moles$\frac{11}{135} \simeq 0.08148 \text{ moles}$
A 1:1 molar ratio dictates that theoretical yield in moles of product directly matches moles of starting material. Converting experimental mass to moles removes the need to calculate theoretical mass, speeding up the final ratio.
Chapter Mix
Class 12 Chemistry: Amines
Class 11 Chemistry: Some Basic Concepts of Chemistry
Q65jee_main_2026_24_january_eveningCyanides and Isocyanides
Given below are two statements :
Statement I : The dipole moment of R-CN is greater than R-NC and R-NC can undergo hydrolysis under acidic medium to produce
arrayc O ∥ R-C-OH. array$$
\begin{array}{c} \mathrm{O} \\ \mathrm {\parallel} \\ \mathrm{R-C-OH.} \end{array}
$$
Statement II : R-CN hydrolyses under acidic medium to produce a compound which on treatment with SOCl₂$SOCl_{2}$ , followed by the addition of NH₃$NH_{3}$ gives another compound(x). This compound (x) on treatment with NaOCl/NaOH gives a product, that on treatment with CHCl₃/KOH/Δ$CHCl_{3}/KOH/\Delta$ produces R-NC
In the light of the above statements, choose the correct answer from the options given below :
A. Both Statement I and Statement II are false
B. Both Statement I and Statement II are true
C. Statement I is true but Statement II is false
D. Statement I is false but Statement II is true
Solution
Core Logic
Statement I: While it is true that the dipole moment of R-CN is greater than R-NC, the hydrolysis of isocyanide (R-NC) under acidic conditions yields a primary amine and formic acid, not a carboxylic acid (R-COOH) with the same alkyl chain intact.
Reaction: R-NC H₃O^+ R-NH₂ + HCOOH$\mathrm{R-NC} \xrightarrow{\mathrm{H}_3\mathrm{O}^+} \mathrm{R-NH}_2 + \mathrm{HCOOH}$
Thus, Statement I is False.
Statement II:
Hydrolysis of Cyanide: R-CN H₃O^+ R-COOH$\mathrm{R-CN} \xrightarrow{\mathrm{H}_3\mathrm{O}^+} \mathrm{R-COOH}$
With SOCl₂$\mathrm{SOCl}_2$: R-COOH SOCl₂ R-COCl$\mathrm{R-COOH} \xrightarrow{\mathrm{SOCl}_2} \mathrm{R-COCl}$
With NH₃$\mathrm{NH}_3$: R-COCl NH₃ R-CONH₂$\mathrm{R-COCl} \xrightarrow{\mathrm{NH}_3} \mathrm{R-CONH}_2$ (Compound x)
The sequence correctly produces R-NC. Thus, Statement II is True.
Step 1: Final Conclusion
Statement I is false but Statement II is true.
Pattern Recognition
Isocyanide hydrolysis breaks the N-C bond, leaving the R group attached to Nitrogen (forming a 1°$1^{\circ}$ amine). The remaining C becomes formic acid.
Consider the following reactions giving major product. Identify the correct reaction.
A.
B.
C.
D.
Solution
Step 1: Evaluate Reaction (1)
Nitration of acetanilide produces primarily the para-isomer because the -NHCOCH₃$-NHCOCH_3$ group is strongly ortho/para directing and sterically hinders the ortho position. The option incorrectly suggests the meta product. (Incorrect)
Step 2: Evaluate Reaction (2)
Gabriel phthalimide synthesis does not work with aryl halides because aryl halides do not readily undergo nucleophilic substitution. Thus, bromobenzene cannot form aniline this way. (Incorrect)
Step 3: Evaluate Reaction (3)
Reaction of secondary amine with CHCl₃/KOH$CHCl_3/KOH$ does NOT yield an isocyanide. The carbylamine test is strictly for primary amines. (Incorrect)
Carbylamine test = 1° amines only. Gabriel Phthalimide = aliphatic 1° amines only (no aryl halides). Hoffmann degradation strictly lowers carbon chain by 1 (CO$CO$ removal).
Chapter Mix
Class 12 Chemistry: Amines
Q63jee_main_2026_28_january_eveningReactions Of Amines
A student performed analysis of aliphatic organic compound 'X' which on analysis gave C = 61.01%$C = 61.01\%$, H = 15.25%$H = 15.25\%$, N = 23.74%$N = 23.74\%$.
This compound, on treatment with HNO₂/H₂O$HNO_{2}/H_{2}O$ produced another compound 'Y' which did not contain any nitrogen atom. However, the compound 'Y' upon controlled oxidation produced another compound 'Z' that responded to iodoform test.
The structure of 'X' is:
Step 1: Empirical Formula calculation:
Moles of C = (61.01)/(12) ≈ 5.08$C = \frac{61.01}{12} \approx 5.08$
Moles of H = (15.25)/(1) ≈ 15.25$H = \frac{15.25}{1} \approx 15.25$
Moles of N = (23.74)/(14) ≈ 1.69$N = \frac{23.74}{14} \approx 1.69$
Ratio C : H : N = (5.08)/(1.69) : (15.25)/(1.69) : (1.69)/(1.69) ≈ 3 : 9 : 1$\frac{5.08}{1.69} : \frac{15.25}{1.69} : \frac{1.69}{1.69} \approx 3 : 9 : 1$
Empirical formula = C₃H₉N$C_3H_9N$.
Step 2: Chemical tests deduction.
The compound is treated with HNO₂/H₂O$HNO_2/H_2O$ and produces a nitrogen-free compound Y. This implies X is a primary aliphatic amine (C₃H₇NH₂$C_3H_7NH_2$), giving an alcohol Y (C₃H₇OH$C_3H_7OH$).
Compound Y upon controlled oxidation forms Z, which gives positive iodoform test. For Z to give an iodoform test, it must be a methyl ketone. Thus Z is acetone (CH₃COCH₃$CH_3COCH_3$).
For Y to oxidize to acetone, Y must be Isopropyl alcohol (CH₃CH(OH)CH₃$CH_3CH(OH)CH_3$).
Therefore, X must be Isopropylamine: (CH₃)₂CHNH₂$(CH_3)_2CHNH_2$.
Step 1: Reaction Sequence
Reactions Of Amines diagram for Q63 - JEE Main 2026 Evening(CH₃)₂CHNH₂ HNO₂ (CH₃)₂CH-N₂^+ -N₂ (CH₃)₂CH^+ H₂O (CH₃)₂CHOH (Y)$(CH_3)_2CHNH_2 \xrightarrow{HNO_2} (CH_3)_2CH-N_2^+ \xrightarrow{-N_2} (CH_3)_2CH^+ \xrightarrow{H_2O} (CH_3)_2CHOH \text{ (Y)}$(CH₃)₂CHOH Oxidation CH₃COCH₃ (Z)$(CH_3)_2CHOH \xrightarrow{\text{Oxidation}} CH_3COCH_3 \text{ (Z)}$CH₃COCH₃$CH_3COCH_3$ responds to the iodoform test.
Step 2: Final Conclusion
The structure of 'X' is Isopropylamine.
Pattern Recognition
Iodoform test on an oxidized alcohol means the alcohol was a secondary alcohol with a terminal methyl group. Combining this with HNO₂$HNO_2$ reacting with primary amines gives the exact functional groups.
Chapter Mix
Class 11 Chemistry: Organic Chemistry - Some Basic Principles and Techniques
Class 12 Chemistry: Amines
Class 12 Chemistry: Aldehydes, Ketones and Carboxylic Acids
More Amines Questions — jee_main_2026_24_january_morning
Practice past-year questions one chapter at a time. Pick an exam → subject → chapter and get every PYQ for that topic — pulled together from all past papers — with the chapter's key formulas alongside.