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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 251. |
Among the following compounds nitrobenzene, benzene, aniline and phenol, the strongest besic behaviour in acid mediu is exhibited byA. PhenolB. AnilineC. NitrobenzeneD. Benzene |
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Answer» Correct Answer - B Because the N atom in amiline has a lone pair to donate and also due to `+I` effect of `-NH_2` group. |
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| 252. |
Primary amine is not formed in the reaction of I. hydrolysis of RCN II. reduction of RCH = NOH III. hydrolysis of RNC IV. hydrolysis of `R CONH_2`The correct answer isA. I , II and IVB. I and IVC. II and IIID. I,II and III |
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Answer» Correct Answer - B `RCN overset("Hydrolysis")to RCOOH + NH_3` `RCH = NOH overset("Reduction")to RCH_2NH_2 + H_2O` `RNC + 2H_2O overset(Delta) to RNH_2 + HCOOH` `RCONH_2 overset("Hydrolysis")to RCOOH + NH_3` |
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| 253. |
Amino group, `-NH_(2)` is ortho, para-directing group in case of aromatic electrophilic substitution but nitration of aniline produce a good amount of m-nitroaniline. This is becauseA. in nitration mixture, ortho-para-activity of -`NH_(2)` group is completely lostB. `-NH_(2)"becomes" -NH_(3)^(+),"which is m-directing"`C. `-NH_(2)"becomes" -NH^(+)SO_(4)^(-),"which is m-directing"`D. `-NH_(2)"becomes" -NH^(-)NO_(2)^(+),"which is m-directing"` |
| Answer» Correct Answer - B | |
| 254. |
The correct order of basicities of the following compounds is , `" "underset((2))(CH_(3)CH_(2)NH_(2))` `underset((3))((CH_(3))_(2)NH)" "underset((4))(CH_(3)CONH_(2))`A. `2 gt 1 gt 3 gt 4`B. `1 gt 3 gt 2 gt 4`C. `3 gt 1 gt 2 gt 4`D. `1 gt 2 gt 3 gt 4` |
| Answer» Correct Answer - B | |
| 255. |
Benzamide on reaction with `POCl_3` givesA. anilineB. chlorobenzeneC. benzylamineD. benzonitrile |
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Answer» Correct Answer - D `POCl_3` is a dehydrating agent. Hence `C_6H_5CONH_2overset(POCl_2)toC_6H_5CN+H_2O` |
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| 256. |
Arrange the following compounds in increasing order of their acidic strength: (i) m-nitrophenol (ii) m-cresol (iii) phenol (iv) m-chlorophenolA. `ii lt iii lt iv lt i`B. `iii lt ii lt I lt iv`C. `ii lt iv lt iii lt i`D. `ii lt iii lt I lt iv` |
| Answer» Correct Answer - A | |
| 257. |
`CHCl_(3)` and KOH on heating with a compound form a bad smelling product compound isA. `C_2H_5CN`B. `C_2H_5NC`C. `C_2H_5OH`D. `C_2H_5NH_2` |
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Answer» Correct Answer - D This is carbylamine reaction which is used to distinguish `1^@` amines from other amines . The reaction is given by `1^@` amines only. `C_2H_5NH_2 + CHCl_3 + 3KOH to C_2H_5N undersetto= C + 3KCl + 3H_2O` `underset(1^@ "amine")(RNH_2) + underset"Chloroform"(CHCl_3) + 3KOH to underset"(bad smelling)"underset"Isocyanide"(RN undersetto=C)+3KCl + 3H_2O` |
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| 258. |
The product formed by the reaction of acetamide with bromine in presence of `NaOH` isA. `CH_3CN`B. `CH_3CHO`C. `CH_3CH_2OH`D. `CH_3NH_2` |
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Answer» Correct Answer - D `CH_3CONH_2+2NaOH+Br_2rarr` `CH_3CONH_2+2NaCO_3+2NaBr+H_2O` |
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| 259. |
The diazonium salts have the general formula _____ Select an appropriate statement in order to complete the above statement.A. `R N_2^(+)X^(-)` , where , R stands for an aryl group and `X^-` ion may be `Cl^-, Br^-, HSO_4^(-), BF_4^-` etc.B. `R_2N^(+)X^(-)` , where , R stands for an aryl group and `X^-` ion may be `Cl^-, Br^-, HSO_4^(-), BF_4^-` etc.C. `R N_2^(+)X^(-)` , where , R stands for an arkyl group and `X^-` ion may be `Cl^-, Br^-, HSO_4^(-), BF_4^-` etc.D. None of the above |
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Answer» Correct Answer - A The diazonium salts have the general formula R `N_2^+X^-`where, R stands for an aryl group and `X^-` ion may be `Cl^- , Br^-, HSO_4^-, BF_4^-` etc. |
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| 260. |
When aqueous solution of benzene diazonium chloride is boiled, the product formed isA. `C_6H_5CH_2OH`B. `C_6H_6+N_2`C. `C_6H_5COOH`D. `C_6H_5OH` |
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Answer» Correct Answer - D When aqueous solution of benzene diazonium chloride is boiled, it gives phenol. |
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| 261. |
Ethylcyanide can be converted into ethylamine by (I)`overset(Sn // HCl)to` (II)`overset(H_3O^(+)) to overset(NH_3, Delta)to overset(KOBr, Delta)to `A. Only IB. Only IIC. Both (a) and (b)D. None of these |
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Answer» Correct Answer - B `undersetunderset"(three C-chain)""Ethyl cyanide"(CH_3CH_2CN) overset(H_3O^+)to underset"Ethanoic acid"(CH_3CH_2COOH) overset(NH_3,Delta) to CH_3CH_2CONH_2 overset(KBr, Delta)to CH_3CH_2NH_2` |
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| 262. |
Hydrolysis of phenylisocyanide formsA. benzoic acidB. formic acidC. acetic acidD. None of the above |
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Answer» Correct Answer - B Hydrolysis of phenylisocyanide forms formic acid. |
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| 263. |
Basic hydrolysis of `CH_3CN` formsA. `CH_3 oversetoversetO(||)CNH_2,NH_3`B. `CH_3 oversetoversetO(||)C OH,NH_3`C. `CH_3 oversetoverset(O)(||)C O^(Theta), NH_3`D. `CH_3 oversetoverset(O)(||)COH, NH_4^+` |
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Answer» Correct Answer - C `{:(CH_3CN+2H_2O to CH_3COOH + NH_3), (" " darr OH^(-)),(" "CH_3COO^-):}` |
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| 264. |
The most unlikely representation of resonance structures of p-nitrophenoxide ion is:A. B. C. D. |
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Answer» Correct Answer - C Is an unlikely structure because N atoms form five bonds and contains positive charge. |
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| 265. |
Which one of the following nitro compounds when react with nitrous acid followed by treatment with alkali produces blue colour?A. 2-methyl-2-nitropropaneB. 2-methyl-1-nitropropaneC. 2-nitropropaneD. nitrobenzene |
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Answer» Correct Answer - C Nitro group attached to secondary carbon atom will give pseudonitrol with `HNO_2` which on further treatment with alkali gives blue colour. `Hundersetunderset(CH_3)|oversetoverset(CH_3)|C-NO_2overset"HONO"to H_3C-underset(NO)underset|overset(CH_3)overset|C-NO_2 overset"NaOH"to underset"Blue colour "(CH_3-undersetunderset(NO_2)|CH-CH_3)` |
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| 266. |
Among the following the weakest base is .A. `C_6H_5CH_2NH_2`B. `C_6H_5CH_2NHCH_3`C. `O_2NCH_2NH_2`D. `CH_3NHCHO` |
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Answer» Correct Answer - C `-NO_2` is strong electron withdrawing group. |
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| 267. |
Which one of the following amines cannot be prepared by Gabriel phtahlimide synthesis?A. EthylamethylamineB. IsopropylamineC. n-propylamineD. Ethylamine |
| Answer» Correct Answer - A | |
| 268. |
Write the mechanism of Hoffmann bromamide reaction. |
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Answer» Hoffmann bromamide reaction : It is a simple way of converting an amide to an amine having one carbon atom less than the starting amide. The reaction is a rearrangement which is brought about by bromide in presence of alkali. It is believed to proceed through the steps shown below. `RCONH_(2)+Br_(2)+3NaOH to RNH_(2)+2NaBr+NaHCO_(3)+H_(2)O` `RCONH_(2) overset(Br_(2)) to underset("N-Bromamide")(RCONHBr) overset(OH^(-)) to R- overset(O) overset(||)C- overset(ө)N-Br` `to underset("Isocyanate")(R-N=C=0 )overset(H_(2)O) to underset("Carbonic acid")(RNHCOOH) overset(-CO_(2)) to RNH_(2)` Mechanism : It is believed to proceed in following via nitrene intermediate. i) `R-CO-NH_(2)+ :O^(-)Br to underset("Bromamide")(R-CO-ddot(N)HBr+OH^(-)` ii) `R- underset(O) underset(||)(C)- underset(H) underset(|)(N)-Br-OH^(ө) to R- underset(O) underset(||)(C)- overset(ө)(N)-Br+H_(2)O` iii) `R- underset(O) underset(||)(C)- overset(ө)(N)-Br to R- underset(O) underset(||)(C)- overset(ddot)(N)+ :overset(ө)Br " Un stable (Nitrene)"` iv) `R- underset(O) underset(||)(C)- N underset("rearrangement") overset("Molecular") to O=C=underset("alkyl isocyanate")(overset(ddot)(N)-R)` v) `R-N-C-O+2:bar(OH) to underset("Primary amine")(R-NH_(2)+CO_(3)^(2-))` |
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| 269. |
In the compound given below the correct order of the acidity of the position X, Y and Z isA. `ZgtXgtY`B. `XgtYgtZ`C. `XgtZgtY`D. `YgtXgtZ` |
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Answer» Correct Answer - B (i) Position (X) is most acidic due to `-COOH` group. `-NH_3^(+)` group at position Y is more acidic than at Z because of presence of electron withdrawing `-COOH` group in close proximity. Hence `-NH_3^(+)` group at position Z is least acidic. |
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| 270. |
How do you make the following convertions ? Chlorophenylmethane to phenylacetic acid |
| Answer» `underset("methane")underset("chloro phenyl")(C_(6)H_(5)CH_(2)Cl) overset(alc.NaCN) to underset("nitrile")underset("phenyl ethane")(C_(6)H_(5)CH_(2)-CN) overset(H_(3)O^(+)) to underset("acetic acid")underset("phenyl")(C_(6)H_(5)-CH_(2)-COOH)` | |
| 271. |
Which could not be directly prepared from 4-bromobenzenediazonium ion?A. BromobenzenB. 1,4-dibromobenzeneC. 4-bromoacetophenoneD. 4-bromofluorobenzene |
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Answer» Correct Answer - C Diazo group cannot be replaced directly by aceto `(CH_3CO-)` group, remaining all groups `(-CN,-Br` and `-F)` can be brought directly. Hence, among the given, 4-bromoacetophenone cannot be prepared directly from corresponding diazonium salt. |
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| 272. |
Aniline on treatment with excess of bromine water givesA. 2,4,6-tribromoanilineB. o-bromoanilineC. 2,4-dibromoanilineD. p-bromoaniline |
| Answer» Correct Answer - A | |
| 273. |
Aniline on treatment with excess of bromine water givesA. 2,4,6-tribromoanilineB. o-bromoanilineC. 2,4-dibromoanilineD. p-bromoaniline |
| Answer» Correct Answer - A | |
| 274. |
Aniline or treatment with nirtous acid `(NaNO_(2)+HCl)` at 273KA. phenolB. nitrobenzeneC. nitrosobenzeneD. benzene diazonium chloride |
| Answer» Correct Answer - B | |
| 275. |
Nitrosobenzene can be isolated from nitrobenzene underA. Metal and acidB. `Zn` dust and `NH_4Cl`C. alkaline sodium arseniteD. Cannot be isolated |
| Answer» Correct Answer - D | |
| 276. |
Product formed in the given reaction isA. B. C. D. |
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Answer» Correct Answer - A Amine group `(-NH_2)` attached with `CH_2` group is more basec, hence first attacked by the CHl molecule. |
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| 277. |
This is calledA. Fries migrationB. Hofmann-degradation reactionC. Ullmann reactionD. Hofmann-Martius Rearrangement |
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Answer» Correct Answer - D Since, the reaction involves conversion of an N, N-dialkylated aniline into o/p-alkylated aniline, so it is an example of hofmann Martius rearrangement. |
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| 278. |
Aniline is usually purified byA. Steam distillationB. Simple distillationC. Vacuum distillationD. Extraction with a solvent |
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Answer» Correct Answer - A Aniline is usually purified by steam distillation. |
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| 279. |
Which one of the following amines can not be prepared by Gabriel synthesis?A. ButylamineB. IsobutylamineC. 2-PhenylethylamineD. N-methylbenzylamine |
| Answer» Correct Answer - D | |
| 280. |
Match the following |
| Answer» A-6,B-4,C-8,D-3,E-1,F-2,G-5,H-7 | |
| 281. |
Silver chloride is soluble in methylamine due to the formation of:A. `[Ag(CH_(3)NH_(2)]Cl`B. `[Ag(CH_(3)NH_(2))_(2)]Cl`C. `[Ag(CH_(3)NH_(2))_(3)]Cl`D. `[Ag(CH_(3)NH_(2))]Cl` |
| Answer» Correct Answer - B | |
| 282. |
Which of the following chemicals are used to manufacture methy1 isocyanate that caused Bhopal Tragedy ? Methylamine (ii) Phosgene (iii) Phosphine (iv) Dimethylamine .A. I and iiB. iii and ivC. I and iiiD. ii and iv |
| Answer» Correct Answer - A | |
| 283. |
Match the following |
| Answer» A-5,B-7,C-1,D-8,E-2,F-4,G-3,H-6 | |
| 284. |
Tertiary amines dissolve in cold nitrous acid to form salt which on warming decomposes to give:A. `R_(3)N.HNO_(2)`B. `R_(2)N.NO`C. `ROH`D. `R_(2)N.NO+ROH` |
| Answer» Correct Answer - D | |
| 285. |
Write the equations involved in the conversion of acetamide and propanaldehydeoxime to methyl cyanide and ethyl cyanide respectively. |
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Answer» `underset("Acetamide")(CH_(3)CONH_(2))+ underset("chloride")underset("sulphonyl")underset("Benzene")(C_(6)H_(5)SO_(2)Cl) overset("pyricline",70^(@)C) to underset("methyl cyanide")(CH_(3)-CN+C_(6)H_(5)SO_(3)H+HCl)` `underset("dehydeoxime")underset("propanal")(CH_(3)-CH_(2)-CH)=underset("Acetic anhydride")(N.OH+(CH_(3)CO)_(2)O) to underset("Ethyl cyanide")(CH_(3)-CH_(2)-CN+2CH_(3)COOH)` |
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| 286. |
The primary, secondary and tertiary amines can be best distinguished byA. `CS_(2)//HgCl_(2)`B. `NaNO_(2)//HCl`C. `CHCl_(3)//KOH`D. `X_(2)//NaOH` |
| Answer» Correct Answer - A::B::C | |
| 287. |
Classify the following amines as primary, secondary or tertiary. iii) `(C_(2)H_(5))_(2)CHNH_(2)` iv) `(C_(2)H_(5))_(2)NH` |
| Answer» i) Primary ii) Tertiary iii) Primary iv) Secondary. | |