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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.
| 401. |
Among the following the most reactive towards alcoholic KOH isA. `CH_(3)CH_(2)Br`B. `(CH_(3))_(2)CHBr`C. `CH_(3)CH_(2)CH_(2)Br`D. `CH_(3)COCH_(2)CH_(2)Br` |
| Answer» Correct Answer - D | |
| 402. |
water (through `S_(N^(2))` reaction mechanism) then sterochemistry of product so formed will be:A. RB. SC. mixture of R and SD. Partial S+ recemic mixture |
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Answer» Correct Answer - A Original compound is (R) hence the product formed will be (S) due to inversion of configuration. |
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| 403. |
Which of the following is least reactive towards nucleophilic substitution with aqueous KOHA. B. C. D. |
| Answer» Correct Answer - B | |
| 404. |
Which of the following compounds is more reactivity in `SN^(1)` reactionA. t-butyl iodideB. Vinyl iodideC. Benzy iodideD. Allyl iodide |
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Answer» Correct Answer - C Compound which produced more stable carbocation is more reactive for `SN^(1)` reaction. Benzyl carbocation is more stable than other. |
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| 405. |
2-Chloro-2-methylpropane on reaction with aqueous KOH gives X as the major product. X isA. but-2-eneB. 2-methylbut-1-eneC. 2-methylprop-1-eneD. 2-methylbutan-2-ol |
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Answer» Correct Answer - C `CH_3-underset(CH_3)underset(|)overset(Cl)overset(|)C-CH_3overset(alc. KOH)tounderset("2-Methylprop-1-ene")(CH_3-underset(CH_3)underset(|)C=CH_2)` |
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| 406. |
Which of the following alkanes can be synthesized by the Wurtz reaction in good yield ?A. `(CH_(3))_(2)CHCH_(2)CH(CH_(3))_(2)`B. `CH_(3)CH_(2)C(CH_(3))_(2)CH_(2)CH_(3)`C. `(CH_(3))_(2)CHCH_(2)CH_(2)CH(CH_(3))_(2)`D. `(CH_(3))_(3)C CH_(2)CH_(2)CH_(3)` |
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Answer» Correct Answer - C Alkane (c) is not only symmetrical, but also has even number of carbons. Hence, it is prepared by Wurtz reaction in good yield. Alkane (a) and (b) are symmetricalbut have an odd number of carbons. Alkane (d) is not symmetrical and also has a odd number of carbons. Consequently, alkanes (a) b (d) cannot be prepared in good yeild by Wurtz reaction |
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| 407. |
Assertion: Replacement fo -Cl group by -OH in chlorobenzene is easier if nitro group is present in the ring. Reason: Nitro group leads to strengthening of the C-Cl bond in chlorobenzene.A. If both assertion and reason are true and reason Is the correct explanation of assertion.B. If both assertion and reason are true but reason is not the correct explanation of assertion.C. If assetion is true but reason is false.D. If both assertion and reason are false. |
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Answer» Correct Answer - C Nitro group is an electron withdrawing group which leads to weakening of C-Cl bond, hence making it easier to replece the -Cl group. |
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| 408. |
Bacause of the resonance stabilization of Arylhalides they are unreactive toward normal nuclephilic substitution reactions . However arylhalides having strong electron withdrawing groups at ortho and para positions give aromatic nucleophilic substitution reactions `(S_(N)Ar` mechanism ) , which involves a resonance stablilized carbanion called Meisenheimer complex Which arylhalide is most reactive toward `S_(N)Ar` mechanism ?A. B. C. D. |
| Answer» Correct Answer - A | |
| 409. |
Bacause of the resonance stabilization of Arylhalides they are unreactive toward normal nuclephilic substitution reactions . However arylhalides having strong electron withdrawing groups at ortho and para positions give aromatic nucleophilic substitution reactions `(S_(N)Ar` mechanism ) , which involves a resonance stablilized carbanion called Meisenheimer complex What would be the product of the given reaction ? A. B. C. D. |
| Answer» Correct Answer - B | |
| 410. |
Bacause of the resonance stabilization of Arylhalides they are unreactive toward normal nuclephilic substitution reactions . However arylhalides having strong electron withdrawing groups at ortho and para positions give aromatic nucleophilic substitution reactions `(S_(N)Ar` mechanism ) , which involves a resonance stablilized carbanion called Meisenheimer complex Which of the following statement is `//` are true ?A. `S_(N)Ar` proceeds through elimination `//` addition mechanismB. Formation of elimination product is the rate determing stepC. Formation of Meisenheimer complex is the rate determining stepD. `S_(N)Ar` mechanism involves inversion of configuration |
| Answer» Correct Answer - C | |
| 411. |
Bacause of the resonance stabilization of Arylhalides they are unreactive toward normal nuclephilic substitution reactions . However arylhalides having strong electron withdrawing groups at ortho and para positions give aromatic nucleophilic substitution reactions `(S_(N)Ar` mechanism ) , which involves a resonance stablilized carbanion called Meisenheimer complex What would be the product of the given reaction ? A. B. C. D. |
| Answer» Correct Answer - B | |
| 412. |
Following compound belonging to the class A. vinyl halideB. allyl halideC. aralkyl halideD. aryl halide |
| Answer» Correct Answer - D | |
| 413. |
IUPAC name of following compound is A. 1-chloro- 1-methyl -2-phenylpropaneB. 3-chloro -2-phenylbutaneC. 2-chloro-3-phenylbutaneD. 2-choro-1,2-dimethylbenzen |
| Answer» Correct Answer - C | |
| 414. |
Halogen derivatives of alkane is known asA. alkyl halidesB. alkenyl halidesC. alkynyl halidesD. aralkyl halides |
| Answer» Correct Answer - A | |
| 415. |
The derivatives not found in nature are :A. alkanesB. carbohydratesC. fatsD. alkyl halides |
| Answer» Correct Answer - D | |
| 416. |
Match List I with List II and pick the correct matching from the codes given below. `{:("List I ",,"List II"),("(Haloalkane"//"arene",,"(Applicaiton)"),("A.Iodoform",,"1."CF_(4)),("B.BHC",,"2.Antiseptic"),("C. Freon-14",,"3.Moth repellent"),("D.Halothanes",,"Inhalative anaesthetic"),("E.p-Dichlorobenzene",,"5.Termite pesticide"):}`A. `A-2,B-4,C-5,D-3,E-1`B. `A-2,B-5,C-1,D-4,E-3`C. `A-3,B-4,C-2,D-1,E-5`D. `A-1,B-3,C-5,D-2,E-4` |
| Answer» Correct Answer - B | |
| 417. |
Assertion: Bromobenzene, upon reaction with `Br_(2)//Fe` gives 1,4-dibromobenzene as the major product. Reason: In bromobenzene, the inductive effect of the bromo group is more dominant than the mesomeric effect in directing the incoming electrophile.A. If both assertion and reason are correct and reason is correct explanation for assertionB. If both assertion and reason are correct but reason is not correct explanation for assertion.C. If assertion is correct but reason is incorrect.D. if both assertion and reason are incorrect. |
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Answer» Correct Answer - C Correct reason: in bromobenzene, the mesomeric effect is more dominant that the inductive effect in directing the incoming electrophile. |
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| 418. |
Which of the following is true about the second order reaction?A. The rate of reaction depends on concentration of `1^(@)R-XandOH^(-)`B. non polar solvent favours this reactionC. Minimum branching and tiny alkyl group can fovours this reactionD. All are true |
| Answer» Correct Answer - D | |
| 419. |
How many bromom derivatives are obtained from b romination of following compound ? A. 2B. 3C. 4D. 5 |
| Answer» Correct Answer - C | |
| 420. |
More reactive haloarenes in electrophilic substitution reaction isA. B. C. D. |
| Answer» Correct Answer - A | |
| 421. |
In haloarenes C-Cl bond has partial double bond character, which is due toA. inductive effectB. electromerticC. resonanceD. steric effect |
| Answer» Correct Answer - C | |
| 422. |
How do polar solvents help in the first step in `S_(N)1` mechanism? |
| Answer» In the `S_(N^(1))` mechanism, a carbocation intermediate is formed in the first step which is a slow step. Polar solvents such as aqueous KOH help in stabilising the carbocation intermediate by solvation. Thus, they favour `S_(N^(1))` mechanism. | |
| 423. |
An alkane with moelcular mass 30 a. m. u. when brominate gives only on monobromiated product. The alkane isA. pentaneB. ethaneC. butaneD. hexane |
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Answer» Correct Answer - B The alkane hasd molecular formula `C_(3)H_(8)` molecular mass 44 gives 2-bromom propane on bromination. |
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| 424. |
Draw the structure of major monohalo product in the reaction `CH_(3)CH_(2) Br + Na I to` |
| Answer» Correct Answer - `CH_(3) CH_(2) l` | |
| 425. |
Among the isomeric alkanes of molecular formula `C_(5)H_(12)`, identify the one that on photochemical chlorination yields (i) A single monochloride. (ii) Three isomeric monochlorides. (iii) Four isomeric monochlorides. |
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Answer» `{:(" "CH_(3)),(" |"),(" "H_(3)C-C-CH_(3)),(" |"),(" "CH_(3)):} " "` All the hydrogen atoms are equivalent and replacement of any hydrogen will give the same product. (ii) `C^(a)H_(3)C^(b)H_(2)C^(c)H_(2)C^(b)H_(2)C^(a)H_(3) " " `The equivalent hydrogens are grouped as a, b and c. The replacement of equivalent hydrogens will give the same product. (iii) `C^(a)H_(3)underset(CH_(3)^(a))underset(|)C^(b)HC^(c)H_(2)C^(d)H_(3) " "` Similarly the equivalent hydrogens are grouped as a, b, c and d. Thus, four isomeric products are possible. |
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| 426. |
Which hydrocarbon is consistent with the following formation ? Molecular mass =72 gives a single monochloride and two dichlorides on photochlorination. |
| Answer» Let the hydrocarbon be `C_(n)H_(2n+3,)` i.e., `12n +2n +2 =72 " or " n =5.`The hydrocarbon is `C_(5)H_(12).` As it forms a single monochloride, all the hydrogen atoms are equivalent . The compound is `(CH_(3))_(4)C` i.e., neopentane. Single chloro derivative is `(CH_(3))_(3)C CH_(2)CI` and the two dichlorides are `(CH_(3))_(3) C CHCI_(2) " and " (CH_(3))_(2)C(CH_(2)CI)_(2)` | |
| 427. |
ter-Alkyl halide is obtained as major product in :A. `(CH_(3))_(3)Choverset(Br_(2))underset(hv)(to)`B. `(CH_(3))_(2)CH-CH=CH_(2)overset(HBr)underset("Peroxide")(to)`C. `(CH_(3))_(2)CH-CH=CH_(2)`D. both (a) and (C) |
| Answer» Correct Answer - D | |
| 428. |
Which of the following is fast de-brominated ?A. B. C. D. |
| Answer» Correct Answer - B | |
| 429. |
Explain how the conversions are carried out : Ethanol to But-1-yne |
| Answer» `CH_(3)underset("Ethanol")(H_(3)- CH_(2)) - OH overset(PCl_(3))(to) underset("Ethyl Chloride")(CH_(3) - CH_(2) -Cl) overset(CH -= C - Na)underset(-NaCl)(to) CH_(3) underset(1-"Butyne")(-CH_(2) - C -=) CH` | |
| 430. |
Explain how the conversions are carried out : Propene to Propanol |
| Answer» `underset("propene")(CH_(3) - CH) = CH_(2) + HBr overset("Peroxide")(to) Cunderset(1 - "Bromopropane")(H_(3) - CH_(2) - CH_(2) - Br) overset("aq." KOH)(to) CH_(3) - underset("Propanol")(CH_(2) - CH_(2)) - OH` | |
| 431. |
Write the structures of the product of the following reactions: (i) `CH_(3)CH=C(CH_(3))_(2)+HBr to ` (ii). `C_(6)H_(5)ON a+C_(2)H_(5)Cl to` |
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Answer» (i). `underset("2,Methylbut-2-ene")(CH_(3)CH=C(CH_(3))_(2)+HB r)tounderset("2-Bromo-2-methylbutane")(CH_(3)-underset(H)underset(|)overset(H)overset(|)(C)-underset(Br)underset(|)overset(CH_(3))overset(|)(C)-CH_(3))` (ii). `underset("Sod. Phenate")(C_(6)H_(5)ON a+C_(2)H_(5)Cltounderset("Ethoxybenzene")(C_(6)H_(5)OC_(2)H_(5)+NaCl` |
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| 432. |
What happens when bromine reacts with `CH_(3)C-=CH?` |
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Answer» Two moles of bromine participate in the reaction. The yellow colour of `Br_(2)` gets discharged. `underset("Propyne")(CH_(3)-C-=CH)+2Br_(2)tounderset("1,1,2,2-Tetrabromopropane")(CH_(3)-underset(Br)underset(|)overset(Br)overset(|)(C)-underset(Br)underset(|)overset(Br)overset(|)(C)H)` |
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| 433. |
When 2-propanol is treated with red phosphorus and bromine givesA. 1-bromo propane and `H_(3)BO_(3)`B. 2-bromo propane and `H_(3)BO_(3)`C. 2-bromo propane and `H_(3)PO_(3)`D. 1-bromo propane and `POBr_(3)` |
| Answer» Correct Answer - C | |
| 434. |
The correct order of reactivity in `S_(N^(1))` reaction for the following compounds is (i). `CH_(3)-underset(Cl)underset(|)(C)H-CH_(2)-CH_(3)` (ii). `Ph-underset(Cl)underset(|)(C)H-CH_(2)-CH_(3)` (iii). `CH_(3)-underset(OC H_(3))underset(|)overset(Cl)overset(|)(C)-CH_(3)` (iv). `CH_(3)-CH_(2)-CH_(2)-Cl`A. `(i)gt(ii)gt(iii)gt(iv)`B. `(ii)gt(i)gt(iii)gt(iv)`C. `(iii)gt(ii)gt(i)gt(iv)`D. `(iv)gt(iii)gt(ii)gt(i)` |
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Answer» Correct Answer - C This order of reactivity in `S_(N^(1))` reactions is directly proportional to the relative stabilities of carbocations in the slow step. `therefore` the correct order of reactivity is: IIIgtIIgtIgtIV |
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| 435. |
Bromination of trans but-2-ene leads to the formation ofA. d-formB. l-formC. meso compoundD. both d and l forms. |
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Answer» Correct Answer - D A meso compound is formed. For detals, consult useful information ofr competitive examinations. |
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| 436. |
Following compound on bromination gives A. B. C. D. |
| Answer» Correct Answer - A | |
| 437. |
Ethylidene chloride is a/an…..A. vic-dihalideB. gem-dihalideC. allylic halideD. vinylic halide. |
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Answer» Correct Answer - B It is a gem (1,1) dihalide. |
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| 438. |
A primary alkyl halide would prefer to undergo :-A. `S_(N^1)` reactionB. `S_(N^2)` reactionC. `prop`-eliminationD. racemisation |
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Answer» Correct Answer - B Primary alkyl halides prefer to undergo `S_(N^2)` reaction. |
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| 439. |
A primary alkyl halide would prefer to undergo :-A. `S_(N^(1))` reactionB. `S_(N^(2))` reaction.C. `alpha`-EliminationD. Racemisation. |
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Answer» Correct Answer - B A primary alkyl halide prefers to undergo `S_(N^(2))` reaction. |
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| 440. |
Assertion: It is difficult to replace chlorine by `-OH` in chlorobenzene in comparison to that in chloroethane Reason: Chlorine-carbon (C-Cl) bond in chlorobenzene has a partial double bond character due to resonance.A. Assertion and reason both are correct and reason is correct explanaion of assertion.B. Assertion and reason both are wrong statements.C. Assertion is correct but reason is wrong statement.D. Assertion is wrong but reason is correct statement. |
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Answer» Correct Answer - A Reason is the correct explanation for assertion |
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| 441. |
What is directional nature of halogen atom when attached to the benzene ring? |
| Answer» Ortho and para directing | |
| 442. |
Out of chlorobenzene and chloroethane which is more readily hydrolysed with aqueous KOH? |
| Answer» Correct Answer - Chloroethane | |
| 443. |
Assertion: Hydrolysis of (-)-2- bromooctane proceeds with inversion of configuration. Reason: This reaction prioceeds through the formation of a carbocation.A. Assertion and reason both are correct and reason is correct explanaion of assertion.B. Assertion and reason both are wrong statements.C. Assertion is correct but reason is wrong statement.D. Assertion is wrong but reason is correct statement. |
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Answer» Correct Answer - C Correct reason: the reaction proceeds through the formation of an intermedeate in the transition state by following `S_(N)2` mechanism. |
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| 444. |
Assertion (A) Hydrolysis of (-)-2-bromooctane proceeds with inversion of configuration Reason (R) This reaction proceeds through the formation of a carbocation.A. Assertion and reason both are correct and reason is correct explanation of assertionB. Assertion and reason both are wrong statementsC. Assertion is correct but reason is wrong statementD. Assertion is wrong but reason is correct statement. |
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Answer» Correct Answer - C Assertion is correct but reason is wrong statement Correct Reason This reaction proceeds through `S_(N)2` mechanism, in which `""^(-)OH` ion attacks at `180^(@)` to the halogen atom of 2-bromooctane which leads to the inversion of configuration. |
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| 445. |
Match the following : `{:("Column I",,"Column II"),("(a) Sandmeyer reaction",,"(p) Chlorobenzene"),("(b) Gattermann reaction",,"(q) Bromobenzene"),("(c) Rasching method",,"(r) Benzyl chloride"),("(d) Chlorination of toluene",,"(s) Iodobenzene"):}` |
| Answer» Correct Answer - `(a-p,q,s);(b-p,q);(c-p);(d-r)` | |
| 446. |
Which of the following compounds are gem-dihalides?A. Ethylidene chlorideB. Ethylene dichlorideC. Methylene chlorideD. Benzyl chloride. |
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Answer» Correct Answer - A::C (a,c) are both gem-dihalides. |
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| 447. |
Alkyl halides are prepared from alcohols by treating withA. `HCl+ZnCl_(2)`B. Red `P+Br_(2)`C. `H_(2)SO_(4)+KI`D. All the above. |
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Answer» Correct Answer - A::B (a,b) both reagents lead to the formation of alkyl halides. |
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| 448. |
Alkyl halides are prepared from alcohols by treating withA. `HCl+ZnCl_(2)`B. Red P+`Br_(2)`C. `H_(2)SO_(4)`+KlD. All of these |
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Answer» Correct Answer - A::B (a) Alcohol when treated with `HCI + ZnCl_(2)` then alkyl halide is formed. `ROH+Hcloverset(ZnCl_(2))tounderset(("Alkyl halide"))(RCl+H_(2)O)` (b) Alcohol when treated with red P and `X_(2)` then product is alkyl halide. `R-Ohoverset("Red P//"Br_(2))tounderset((" Alkyl halide"))(R-X)` (c) Alcohols when treated with `H_(2)SO_(4)` and KI then `H_(2)SO_(4)`, oxidises Kl to `I_(2)` and does not produce Hl. therefore, alkylide does not form if the alcohols are treated with `H_(2)SO_(4)+KI`. |
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| 449. |
When 3-Phenylpropene reacts with HBr in the presence of an organic peroxide, the major product formed is:A. 2-Bromo-1-phenylpropaneB. 1,2-Dibromo-3-phenylpropaneC. 3-(o-bromophenyl)propaneD. 1-Bromo-3-phenylpropane |
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Answer» Correct Answer - D `C_(6)H_(5)-CH_(2)-CH=CH_(2)underset(("peroxide"))overset(HBr)toC_(6)H_(5)-CH_(2)-CH_(2)-CH_(2)-Br.` |
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| 450. |
Ethylidene chloride on hydrolysis with aq. KOH gives ,A. `CH_(3)CHO`B. `CH_(3)COOH`C. `CHCl_(3)`D. `CH_(3)CH_(2)OH` |
| Answer» Correct Answer - A | |