Organic Compounds Containing Nitrogen Mock Test – NEET Chemistry

1. The following qualitative observations are made for three nitrogen-containing compounds in separate aqueous systems.

Which inference is supported by these observations?

2. Two aqueous solutions P and Q are prepared at the same temperature.
P contains an amine with .
Q contains an amine with .
Both solutions are diluted by the same factor while the temperature remains constant.
Consider the following statements.
Statement I: P represents the stronger base.
Statement II: The pKb value of P is one unit smaller than that of Q.
Statement III: Dilution by the same factor necessarily makes the Kb values of P and Q equal.
Statement IV: The ratio of their Kb values remains unchanged after dilution at constant temperature.
Which statements are correct?

3. The following experimental observations are obtained for four separate amines.

A student proposes the following deductions.
Statement I: Both P and Q are structurally eligible for a positive carbylamine reaction despite their different ring substituents.
Statement II: The nitro group in P and the methyl group in Q need not influence nitrogen basicity in the same direction.
Statement III: R and S can both undergo ordinary N-acylation because each possesses an available nitrogen lone pair.
Statement IV: S forms an ordinary Hinsberg sulphonamide, whereas R does not, because their nitrogen-bound hydrogen availability differs.
Which combination is correct?

4. Two aromatic compounds are subjected to ordinary carbylamine testing and subsequently to N-acetylation:
P: 4-Aminobenzyl alcohol, .
Q: N-(4-Hydroxymethylphenyl)ethanamide, .
Assume the hydroxymethyl group remains unchanged during the specified diagnostic reactions.
Which statement correctly distinguishes their nitrogen functionalities and the expected outcomes?

5. Equal concentrations of chloroethane, bromoethane and iodoethane are separately treated with ethanolic ammonia under otherwise identical ammonolysis conditions.
In a second set of reactions, the ammonia-to-haloalkane ratio is increased substantially for each substrate.
Which statement correctly distinguishes the two effects?

6. An unknown amine X gives a negative carbylamine test. On treatment with benzenesulphonyl chloride in aqueous alkali, an insoluble organic layer remains.
A student immediately concludes that X is a secondary amine.
Which additional observation would most directly determine whether the insoluble material is a secondary-amine sulphonamide or unreacted tertiary amine?

7. A mixture contains equal amounts of aniline and benzylamine dissolved in water at . Its pH is maintained at 6.00.
Given:


For an amine B and its conjugate acid :

Which statement best describes the predominant nitrogen-containing forms of the two compounds?

8. Equal analytical concentrations of aniline and ethanamine are present in a buffered aqueous solution at pH 7.00 and .
The conjugate-acid pKa values are:


For an amine B, the fraction present as the neutral free base is:

Using and , what is the approximate ratio of the neutral free-base concentrations?

9. A solution of N-methylaniline is first treated with sufficient hydrochloric acid to obtain its protonated salt P. Two separate samples of P are then subjected to the following treatments.
Treatment I: Addition of aqueous sodium hydroxide, followed by isolation of the free amine.
Treatment II: Addition of methyl iodide without any prior neutralisation, under conditions allowing only ordinary nucleophilic substitution.
Which statement is correct?

10. 4-Chloroacetanilide, , is subjected to controlled mononitration under conditions favouring substitution directed by the acetamido group.
The principal mononitrated derivative is isolated and subsequently hydrolysed to regenerate the free aromatic amino group.
Which product is obtained predominantly?

11. A freshly prepared cold solution contains of benzenediazonium chloride.
Exactly of phenol is added under suitable alkaline azo-coupling conditions.
Assume phenol couples quantitatively with an equal amount of diazonium salt to produce one mole of azo compound per mole of phenol.
The remaining unreacted diazonium salt is then warmed sufficiently with water to undergo quantitative hydrolysis to phenol with nitrogen evolution.
All evolved nitrogen is collected at STP.
Given molar volume at STP .
What are the amount of azo compound formed and the volume of nitrogen gas evolved, respectively?

12. A chemist synthesises an azo compound by coupling benzenediazonium chloride with aniline.
The isolated product is then subjected to a carbylamine test and, in a separate portion, to controlled N-acetylation using ethanoyl chloride and pyridine.
Assume the ordinary para-aminoazobenzene product is obtained in the coupling step and that the azo linkage remains intact during subsequent reactions.
Which statement correctly predicts the outcomes?

13. Bromoethane is reacted separately with potassium cyanide and silver cyanide.
For this question, assume that potassium cyanide produces the corresponding alkyl nitrile, while silver cyanide produces the corresponding alkyl isocyanide.
The products are then treated as follows:
P: The nitrile is reduced completely with , followed by work-up.
Q: The isocyanide is hydrolysed completely under suitable acidic conditions, producing a primary amine and methanoic acid.
Which statement correctly identifies the nitrogen-containing products and the difference in their carbon counts?

14. A mixture of two compounds is analysed by quantitative nitrogen evolution with nitrous acid:
P: 2-Aminoethanoic acid, .
Q: N-Methyl-2-aminoethanoic acid, .
Both contain carboxylic acid groups, but P contains a primary aliphatic amino group whereas Q contains a secondary amino group.
A sample contains of P and of Q.
Assume that P liberates one mole of nitrogen gas per mole through its ordinary primary-aliphatic-amine nitrous-acid reaction, while Q forms an N-nitroso derivative without nitrogen-gas evolution under the stipulated conditions.
What percentage of the original nitrogen atoms in the entire sample leave as molecular nitrogen?

15. Four statements are made concerning amines, their physical properties and their conversion into ammonium salts.
Statement I: Formation of an ammonium salt can greatly increase the apparent aqueous solubility of an amine.
Statement II: Primary and secondary amines can form intermolecular N–H···N hydrogen bonds because they contain nitrogen-bound hydrogen atoms and nitrogen lone pairs.
Statement III: Tertiary amines cannot form hydrogen bonds with water because they do not contain nitrogen-bound hydrogen atoms.
Statement IV: The boiling-point order of suitable isomeric amines cannot be applied without qualification to amines having substantially different molecular masses.
Which combination is correct?

16. Nitrobenzene undergoes the following three-stage sequence:



The acylation in the second stage is performed under conditions suitable for obtaining the corresponding N-acyl derivative.
What is compound R?

17. Two aromatic compounds are to be prepared from aniline:
P: Nitrobenzene.
Q: 4-Nitroaniline.
For P, the available method is diazotisation followed by conversion of the diazonium chloride into its tetrafluoroborate and treatment with aqueous sodium nitrite and copper under the appropriate nitro-replacement conditions.
For Q, the available method is acetylation of aniline, controlled nitration and subsequent hydrolysis.
Which statement correctly explains why the two routes are not interchangeable?

18. A mixture contains nitrobenzene and benzonitrile, with a total amount of . The mixture is subjected to catalytic hydrogenation using sufficient nickel catalyst and exactly of hydrogen. Both organic compounds are completely converted into their corresponding primary amines, and all the supplied hydrogen is consumed.
Assume no other hydrogen-consuming reactions occur.
What were the initial amounts of nitrobenzene and benzonitrile, respectively?

19. A chemist is given 2-aminophenol, which contains a primary aromatic amino group and a phenolic hydroxyl group at adjacent ring positions.
Two separately isolated derivatives are prepared under explicitly selective conditions.
P: Only the amino nitrogen is acetylated using ethanoic anhydride.
Q: Only the phenolic oxygen is acetylated using ethanoic anhydride.
Both derivatives are then independently tested for ordinary primary-aromatic-amine diazotisation and for ordinary conversion of a free phenolic hydroxyl group into phenoxide using aqueous sodium hydroxide.
Assume that neither acetyl group is hydrolysed during testing.
Which statement correctly predicts the distinguishing outcomes?

20. An optically active sample of butan-2-yl bromide is divided into two portions.
Pathway P: The alkyl bromide undergoes complete substitution with ammonia through an exclusively pathway, followed by liberation of the free amine.
Pathway Q: The alkyl bromide undergoes complete substitution with potassium cyanide through an exclusively pathway, followed by complete nitrile reduction using .
Assume that neither pathway involves racemisation or rearrangement and that reduction of the nitrile does not alter the stereogenic carbon.
Which statement correctly compares the final products?

21. Optically active 2-aminobutanoic acid is treated with sufficient nitrous acid under conditions giving the corresponding 2-hydroxybutanoic acid with nitrogen evolution.
The isolated hydroxy acid is then oxidised under conditions that convert its secondary alcohol group into a ketone while preserving the carboxylic acid group.
Which statement correctly identifies the final functional groups and the effect on the stereogenic carbon originally bearing the amino group?

22. A substituted arenediazonium salt is reacted separately with two compounds:
P: 4-Methylphenol.
Q: 2,6-Dimethylphenol.
Both reactions are performed under conditions favouring ordinary azo coupling at an available ortho or para position relative to hydroxyl.
Which statement correctly compares the likely coupling positions and explains the influence of the methyl substituents?

23. A chemist needs to prepare benzylamine, , and aniline, , separately as primary amines. The chemist wants to use Gabriel phthalimide synthesis for one product and nitro-group reduction for the other.
Which selection of starting materials and preparation methods is chemically appropriate?

24. A substituted aromatic compound contains a free primary amino group and a methoxy group at para positions.
Its amino group is protected by acetylation, after which the ring is subjected to controlled electrophilic bromination.
Assume that the initially para methoxy and acetamido groups remain intact and that the substituent directing effects are:
: ortho/para directing.
: ortho/para directing.
Steric conditions favour substitution at an available site ortho to methoxy rather than ortho to acetamido.
Which aromatic positions are selected if the acetamido-bearing carbon is numbered 1 and the methoxy-bearing carbon is numbered 4?

25. Three aromatic amino compounds have the following structures:
P:
Q:
R:
A student compares the electronic influences of their ring substituents and nitrogen functionalities.
Which statement is correct?

26. Two compounds are represented by the following systematic names:
P: N-Ethyl-3-methylbutan-2-amine
Q: N,N-Dimethylpentan-2-amine
Which statement correctly compares their molecular formulas and nitrogen substitution degrees?

27. Benzenediazonium chloride is coupled separately with phenol and 4-methylphenol under suitable alkaline conditions.
In both cases, assume ordinary electrophilic aromatic coupling and that the activated aromatic positions remain available except where already occupied by substituents.
Which statement correctly predicts the preferred coupling positions?

28. 4-Nitroaniline is subjected to bromination using sufficient bromine under conditions that introduce bromine at both available positions ortho to its amino group. The isolated dibrominated compound is then treated with , followed by sufficient aqueous sodium hydroxide.
Assume the bromine substituents remain unchanged during reduction.
What is the final organic product?

29. A mixture contains three constitutional isomers with molecular formula :
P: Butan-1-amine.
Q: N-Ethylethanamine.
R: N,N-Dimethylethanamine.
Under specially stipulated conditions, every nitrogen-bound hydrogen atom in each molecule is quantitatively exchanged for deuterium using excess , while all carbon-bound hydrogen atoms remain unchanged.
Take the mass difference between D and H as .
The mixture contains of P, of Q and of R.
What is the increase in the total mass of the mixture after exchange?

30. Four halogen-containing compounds are considered for Gabriel phthalimide synthesis under conventional nucleophilic substitution conditions.
Statement I: Bromoethane can be used to prepare ethanamine.
Statement II: Bromobenzene can be used directly to prepare aniline.
Statement III: Benzyl bromide can be used to prepare benzylamine.
Statement IV: 2-Bromo-2-methylpropane is a suitable substrate for an efficient ordinary Gabriel substitution to prepare 2-methylpropan-2-amine.
Which statements are correct?

31. A sample contains of hexane-1,6-diamine and of ethanamine.
Both compounds are treated with sufficient nitrous acid under conditions that quantitatively convert every primary aliphatic amino group into an alcohol group with evolution of one mole of nitrogen per amino group.
Assume no rearrangement, cyclisation or competing reaction occurs, and all nitrogen gas is collected at STP.
Given molar volume at STP .
What volume of nitrogen gas is obtained?

32. The following conversion is proposed:

Assume that the pre-existing aromatic C–Cl bond remains unchanged throughout the sequence.
Which statement correctly identifies P, Q and R?

33. Two substituted anilines P and Q have their aqueous basicities compared.
P contains a para-methyl group, while Q contains a para-nitro group.
The student proposes the following conclusions.
Statement I: The para-methyl group generally increases electron density and can favour the basicity of P relative to unsubstituted aniline.
Statement II: The para-nitro group withdraws electron density and generally weakens the basicity of Q relative to aniline.
Statement III: The stronger base must always undergo electrophilic aromatic substitution faster under any acidic reaction conditions because basicity and ring activation are identical properties.
Statement IV: Strongly acidic conditions can protonate the amino group and change its directing influence during aromatic substitution.
Which combination is correct?

34. Three amines are subjected separately to the reaction with nitrous acid generated in situ from sodium nitrite and dilute hydrochloric acid under suitable conditions.
P:
Q:
R:
Which option correctly describes their characteristic reactions?

35. Direct nitration of aniline using a concentrated nitric acid–sulfuric acid mixture may produce significant quantities of the meta-nitro derivative, even though the free amino group is ortho/para directing.
Which explanation correctly accounts for this observation?

36. The pKb values of three amines in water at 298 K are supplied:

A student claims that the aqueous basicity order should be R Q P because increasing alkyl substitution always increases the positive inductive effect.
Which statement correctly identifies the strongest aqueous base and the conceptual defect in the student's reasoning?

37. A reaction scheme begins with 4-bromoacetanilide, .
The compound undergoes hydrolysis to regenerate its free aromatic amino group. The isolated product is then treated with sufficient bromine water at room temperature.
Assume complete substitution at the remaining strongly activated, unoccupied ortho positions of the amino group.
What is the principal final organic product?

38. Two solutions contain equal analytical concentrations of aniline and N,N-dimethylaniline, respectively.
The following aqueous pKb values at 298 K are supplied:


Assume the solutions are sufficiently dilute to apply the ideal weak-base equilibrium model, with water autoionisation negligible.
Which statement correctly compares their hydroxide-ion concentrations at equal analytical concentration and explains why the comparison cannot be reduced to counting N–H bonds?

39. An organic mixture contains a neutral tertiary amine P and a quaternary ammonium chloride Q.
P has the structure , whereas Q has the formula .
Each is treated separately with sufficient aqueous sodium hydroxide at room temperature under ordinary acid–base conditions.
Which statement correctly distinguishes the expected nitrogen-containing species?

40. Freshly prepared aniline and an aromatic azo dye are separately stored in transparent containers under ordinary laboratory conditions.
The freshly prepared aniline sample is initially nearly colourless but gradually develops colour on exposure to air.
The azo dye is already coloured before storage.
A student concludes that both colours must arise from the same azo linkage formed during storage.
Which statement correctly evaluates the conclusion?

41. A substituted aromatic diazonium salt is represented as:

It is subjected to controlled thermal decomposition to form an aromatic fluoride.
The product is then oxidised with hot alkaline potassium permanganate, followed by acidification.
Assume the aromatic fluorine substituent is not displaced and the methyl side chain is quantitatively converted into a carboxylic acid.
Which statement correctly identifies the final product and describes the sources of its functional groups?

42. Two aromatic compounds are compared:
P: 2-Methylbenzenamine.
Q: N-Methylbenzenamine.
Each is separately treated with ethanoyl chloride and pyridine under conditions allowing complete ordinary N-acetylation.
The acetylated products are then subjected to controlled aromatic bromination.
Which statement correctly describes the different locations of their original methyl groups and the nitrogen functionalities after acetylation?

43. A freshly prepared aqueous solution contains of benzenediazonium chloride.
It is warmed to a temperature at which hydrolysis to phenol follows a stipulated first-order decay law:

At that temperature, the half-life of the diazonium salt is .
After , the mixture is cooled and the remaining diazonium salt is coupled quantitatively with sufficient phenol.
Assume that hydrolysis produces one mole of nitrogen per mole of diazonium consumed, whereas coupling retains the diazonium nitrogen atoms.
What are the moles of nitrogen gas evolved during warming and the moles of azo product formed subsequently, respectively?

44. Two constitutional isomers of molecular formula are represented as:
P:
Q:
Each compound is separately treated with sufficient benzoyl chloride in pyridine under conditions giving one ordinary N-benzoylation per nitrogen atom possessing an available N–H bond.
Which statement correctly compares their nitrogen classifications and the numbers of benzoyl groups introduced?

45. Two compounds have the same molecular formula, .
P is 2-aminophenol, in which the amino and hydroxyl groups occupy adjacent positions on a benzene ring.
Q is 4-aminophenol, in which these groups occupy para positions.
Both contain free primary aromatic amino groups.
Which statement correctly combines their hydrogen-bonding possibilities with their amine classification?

46. An unknown saturated acyclic compound X contains two nitrogen atoms and has the molecular formula .
Under suitable conditions, it gives a negative ordinary carbylamine test.
It consumes two equivalents of hydrochloric acid per mole when both nitrogen centres are completely protonated.
It undergoes ordinary N-benzoylation at both nitrogen centres, introducing exactly two benzoyl groups per molecule.
Which structure is consistent with all observations?

47. An organic compound having the structure is subjected to catalytic hydrogenation using under conditions suitable for reducing the nitro group. The principal organic product is:

48. A chemist proposes two routes for preparing N-methylethanamine from nitromethane.
Route P:
(i) Reduce nitromethane to methanamine.
(ii) Acetylate methanamine to form N-methylethanamide.
(iii) Reduce the amide carbonyl with .
Route Q:
(i) Reduce nitromethane to methanamine.
(ii) React the methanamine with excess methyl iodide until complete quaternisation.
(iii) Treat the resulting quaternary ammonium salt with aqueous sodium hydroxide.
Which statement correctly evaluates these routes?

49. Aniline and acetanilide are subjected separately to controlled aromatic nitration. In a second experiment, aniline is first converted into its hydrochloride salt and then subjected to the same strongly acidic nitrating medium.
Which statement correctly relates the nitrogen substituent's electronic state to the nitration outcomes?

50. A mixture contains trimethylammonium chloride, , and tetramethylammonium iodide, .
The total amount of the two salts is .
A separate portion having the same composition is treated with sufficient aqueous sodium hydroxide under conditions that completely liberate trimethylamine from its hydrochloride but do not cleave N–C bonds in the quaternary ammonium salt.
Exactly of volatile trimethylamine is recovered.
The original mixture is then treated with excess silver nitrate, precipitating chloride and iodide quantitatively as and .
What is the total amount of silver halide precipitate?