InterviewSolution
Saved Bookmarks
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. |
It is not always easy to predict the position of attack on multiply substituted benzene. If the benzene ring bears different ortho//para directing group at the `1` and `4` positions, the position of further substitution is not immediately clear. Sometimes steric effects determine the outcome. In other cases, electronic factors determine the outcome, and further reaction will be at the position activated by the more strongly activating group. Some substituens are so strongly activating that no catalyst is needed, and it is often diffcult to stop substitution after mono substituion. Mild condition are needed to restrict the reaction to mono-substitution. It is possible to reduce the activity such groups by side chain reaction so that the reaction can be stopped use can sometimes be made of removable blocking groups on the ring. Which of the following synthesis could be done in the ring step ?A. B. C. D. |
| Answer» Correct Answer - C | |
| 252. |
Consider the following reaction: `CH_(3)underset(D)underset(|)CH-underset(CH_(3))underset(|)(CH)CH_(3)+overset(.)BrrarrX+HBr` Identify the structure of the major products `(X)` from among the following :A. `H_(3)C-underset(D)underset(|)CH-underset(CH_(3))underset(|)CH-overset(*)CH_(2)`B. `H_(3)C-underset(D)underset(|)CH-underset(CH_(3))underset(|)overset(*)C-CH_(3)`C. `H_(3)C-underset(D)underset(|)overset(*)C-underset(CH_(3))underset(|)(CH)-CH_(3)`D. `H_(3)C-overset(*)CH-underset(CH_(3))underset(|)(CH)-CH_(2)` |
| Answer» Correct Answer - B | |
| 253. |
Give the structure of the major organic products obtained from `3-`ethyl`-2-`pentene under each of the following reaction conditions. `a.` `HBr` in the presence of peroxide `b.` `Br_(2)//H_(2)O` `c.` `Hg(Oac)_(2)//H_(2)O,NaBH_(4)` |
|
Answer» Correct Answer - (a) `(CH_(3)-CH_(2))_(2)CH-overset(Br)overset(|)CH-CH_(3)` (b) `(CH_(3)-CH_(2))_(2)overset(OH)overset(|)C-overset(Br)overset(|)CH-CH_(3)` (c) `(C_(2)H_(5))_(3)-C-OH` |
|
| 254. |
The origin of acidity and basicity in organic compound is great interest and provides an extensive comparison. Among hydrocarbons `%` a character is taken in aC Count while to decide the acidity, in simple aliphatic acids, more the number of alkyl groups, (+1 effect) less is the acidity `&` more the (-1 effect) groups larger the acidity and vice-versa in the case of simple alphatic bases. Benzoic acid is more stronger than carboxylic acid as benzoate ion is stablised more by resonance. Aromatic amines are less basic than apiphatic amine as the electron pair is less available in case of aromatic amines. The presence of solvent also plays a very important role and at time governs the order too. Amongst the following the most basic compound is -A. B. C. D. |
| Answer» Correct Answer - B | |
| 255. |
The origin of acidity and basicity in organic compound is great interest and provides an extensive comparison. Among hydrocarbons `%` a character is taken in aC Count while to decide the acidity, in simple aliphatic acids, more the number of alkyl groups, (+1 effect) less is the acidity `&` more the (-1 effect) groups larger the acidity and vice-versa in the case of simple alphatic bases. Benzoic acid is more stronger than carboxylic acid as benzoate ion is stablised more by resonance. Aromatic amines are less basic than apiphatic amine as the electron pair is less available in case of aromatic amines. The presence of solvent also plays a very important role and at time governs the order too. Which of the following is most acidicA. B. C. D. |
| Answer» Correct Answer - B | |
| 256. |
The increasing order of basicity of `RCN,RCH=NR` and `RNH_(2)` is :-A. `RCNltRCH=NRltRNH_(2)`B. `RNH_(2)ltRCNltRCH=NR`C. `RCH=NRltRNH_(2)ltRCN`D. `RH_(2)NltRCH=NRltRCN` |
| Answer» Correct Answer - A | |
| 257. |
The synthesis of 3-octyne is achieved by adding a bromoalkane into a mixture of sodium amide and alkyne. The bromoalkane and alkyne, respectively, areA. `BrCH_(2)CH_(2)CH_(2)CH_(2)CH_(3)` and `CH_(3)CH_(2)C-=CH`B. `BrCH_(2)CH_(2)CH_(3)` and `CH_(3)CH_(2)CH_(2)C-=CH`C. `BrCH_(2)CH_(2)CH_(2)CH_(3)` and `CH_(3)C-=CH`D. `BrCH_(2)CH_(2)CH_(2)CH_(3)` and `CH_(3)CH_(2)C-=CH` |
| Answer» Correct Answer - D | |
| 258. |
In allene `(C_(3)H_(4))`, the type(s) of hybridisation of the carbon atoms, is (are)A. `sp` and `sp^(3)`B. `sp` and `sp^(2)`C. only `sp^(2)`D. `sp^(2)` and `sp^(3)` |
| Answer» Correct Answer - B | |
| 259. |
Aldehyde, ketone, acid and acid derivatives contain `gtC=O` group. Aldehyde and ketones gives nucleop addition reactions where as acid and acid derivatives gives nucleophilic addition followed by ellmination reaction Nucleophilic addition reactions followed by ellimination of acid derivatives is known as acyl substitution reacts This subsitution reaction takes places by formation of tertrahedral intermediate. Which one of the following is least reactive compound for nucleophilic acyl substitution.A. B. C. D. |
| Answer» Correct Answer - B | |
| 260. |
Symmetrically subsituted epoxides give the same products in both the acid catalysed and base catalyzed ring opening. An unsymmetrical epoxide gives different products under acid catalysed and base catalysed conditions. Under basic contions, the alkoxide ion simply attacks the less hindered carbon atom in an `SN^(2)` displacement. Under acidic conditions, the alcohol, attacks the protonated epoxide. Structure II and III show that the oxtrane carbon share part of positive charge. The tertiary carbon bear a larger part of positive charge and it is more strongly electrophilic. The bond between teritiary carbon and oxygen is weaker implying a lower transition state energy for attack at the teritary carbon. Attack by the weak nucleophilic is sensitive to the strength of electrophilic is sensitive to the strength of electrophile. Center attack takes place at more electrophilic carbon which is usually the more substituted carbon because it can better support the positive charge. A. B. C. D. |
| Answer» Correct Answer - A | |
| 261. |
Symmetrically subsituted epoxides give the same products in both the acid catalysed and base catalyzed ring opening. An unsymmetrical epoxide gives different products under acid catalysed and base catalysed conditions. Under basic contions, the alkoxide ion simply attacks the less hindered carbon atom in an `SN^(2)` displacement. Under acidic conditions, the alcohol, attacks the protonated epoxide. Structure II and III show that the oxtrane carbon share part of positive charge. The tertiary carbon bear a larger part of positive charge and it is more strongly electrophilic. The bond between teritiary carbon and oxygen is weaker implying a lower transition state energy for attack at the teritary carbon. Attack by the weak nucleophilic is sensitive to the strength of electrophilic is sensitive to the strength of electrophile. Center attack takes place at more electrophilic carbon which is usually the more substituted carbon because it can better support the positive charge. A. B. C. D. None |
| Answer» Correct Answer - D | |
| 262. |
Arrange the following in order of decreasing acidic strength. P-nitrophenol (I), m-cresol (III),phenol(IV):A. `IgtIVgtIII`B. `IVgtIIIgtIIgtI`C. `IgtIIIgtIIgtIV`D. `IIIgtIIgtIgtIV` |
| Answer» Correct Answer - A | |
| 263. |
Which of the following does not undergo Hell-Volhard Zelinsky reaction?A. HCOOHB. `C Cl_(3)COOH`C. `C_(6)H_(5)COOH`D. All |
| Answer» Correct Answer - D | |
| 264. |
Which compound exhibits maximum dipole moment among the following:-A. B. C. D. |
| Answer» Correct Answer - C | |
| 265. |
Which statement is not true for primary aminesA. These forms salt will acidsB. Gives alcohols on hydrolysisC. Gives carbyl amine reactionD. Gives musturd oil test |
| Answer» Correct Answer - B | |
| 266. |
Amines are derivatives of ammonia and are classified as `1^(@), 2^(@)`, and `3^(@)`, Primary and secondary (but not teritiary amines) form intermolecular hydrogen bonds and thus they boil at highter temperatures than expected. Like ammonia, all amines are basic, although they differ in their basic nature. As amines are considered as derivatives of ammonia, quaternary ammonium salts are considered as derivatives of ammonium salts. Only the quaternary ammonium salts can shown optical activity. When nitrogen is bounded to three different groupsA. The molecule is optically inactiveB. The molecule is tetrahedralC. The molecule is not superimposable on its mirror imageD. The amine boils at nearly similar b.p as the `1^(@)`, and `2^(@)` amine of comparable molecular weight. |
| Answer» Correct Answer - C | |
| 267. |
Consider the following Cannizzaro reaction `2Ph-CHOoverset(OH^(-))rarrPh-CH_(2)OH+PhCO_(2)^(-)` In the above reaction, the slowest step of the reaction isA. the attack of `.^(o+)OH` at the carbonyl groupB. the transfer of hydride to the carbonyl groupC. the abstraction of proton from the carboxylic acidD. the deprotonation of `Ph-CH_(2)OH` |
| Answer» Correct Answer - B | |
| 268. |
`(CH_(3))_(2)overset(Cl)overset(|)C-CH_(2)CH_(3)overset("aic" XOH)rarr `? |
| Answer» Correct Answer - `CH_(3)-underset(CH_(3))underset(|)C=CH-CH_(3)` | |
| 269. |
Isomers of hexane , based on their branching can be divided into three distinct classes as shown in the figure. The correct order of their boiling points is :A. `IgtIIgtIII`B. `IIIgtIIgtI`C. `IIgtIIIgtI`D. `IIIgtIgtII` |
| Answer» Correct Answer - B | |
| 270. |
The correct decreasing order of their reactivity towards hydrolysis is A. `PhCOClgtp-O_(2)NC_(6)H_(4)COClgtp-CH_(3)OC_(6)H_(4)COCl`B. `PhCOClgtp-CH_(3)OC_(6)H_(4)COClgtp-O_(2)NC_(6)H_(4)COCl`C. `P-O_(2)NC_(6)H_(4)COClgtPhCOClgtp-CH_(3)OC_(6)H_(4)COCl`D. `p-O_(2)NC_(6)H_(4)COClgtp-CH_(3)OC_(6)H_(4)COCLgtPhCOCl` |
| Answer» Correct Answer - C | |
| 271. |
In the following reactions. Identify the compounds A, B, C and D`PCl_(5)+SO_(2)toA+B` `A+CH_(3)COOHtoC+SO_(2)+HCl` `2C+(CH_(3))_(2)Cdrarr2D+CdCl_(2)`A. `SOCl_(2), POCl_(3), CH_(3)COCl, CH_(3)COCH_(3)`B. `SOCl_(2), HCl, CH_(3)Cl, CH_(3)CHO`C. `SO_(2),Cl_(2),C_(2)H_(5),Cl, CH_(3)COCH_(3)`D. None of these |
| Answer» Correct Answer - A | |
| 272. |
Which of the following is the most reactive towards ring nitration ?A. B. C. D. |
| Answer» Correct Answer - B | |
| 273. |
In the chemical reactions the compounds `(A)` and `(B)` are .A. Nitrobenzene and chlorobenzeneB. Nitrobenzene and fluorobenzeneC. Phenol and benzeneD. Benzene diazonium chloride and fluorobenzene |
| Answer» Correct Answer - D | |
| 274. |
The strongest deactivating effect on benzene ring isA. `CH_(2)Cl`B. `-OCH_(3)`C. `-CH_(3)`D. `-C Cl_(3)` |
| Answer» Correct Answer - D | |
| 275. |
In the following compounds the order of basicly isA. `IVgtIgtIIIgtII`B. `IIIgtIgtIVgtII`C. `IIgtIgtIIIgtIV`D. `IgtIIIgtIIgtIV` |
| Answer» Correct Answer - D | |
| 276. |
Among the following, which is the strongest acid?A. `CHF_(2)-CH_(2)-CH_(2)-COOH`B. `CH_(3)-CH_(2)-CF_(2)-COOH`C. `CH_(2)F-CHF-CH_(2)-COOH`D. `CH_(3)-CF_(2)-CH_(2)-COOH` |
| Answer» Correct Answer - B | |
| 277. |
Benzene diazonium chloride on reaction with phenol in a basic medium gives:A. Diphenyl etherB. p-HydroxyazobenzeneC. ChlorobenzeneD. Benzene |
| Answer» Correct Answer - B | |
| 278. |
The positive carbylamine test is not given byA. N, N-dimethylanilineB. 2,4-hyroxyazobenzeneC. N-methyl-o-methylanilineD. p-methylbenzylamine |
| Answer» Correct Answer - A::B::C | |
| 279. |
A positive carbylamine test is given by:A. N,N-DimethylanilineB. 2,4-DimethylanilineC. N-Methyl-o-methylanilineD. o-methylbenzylamine |
| Answer» Correct Answer - B::D | |
| 280. |
Which of the following will not react with an ammonical silver nitrate solution :A. `CH_(3)C=CH`B. `(CH_(3))_(2)CH-C=H`C. `CH_(3)C=C CH_(3)`D. `HC=CH` |
| Answer» Correct Answer - C | |
| 281. |
Silver Miror test is given by which one of the following compounds?A. FormaldehydeB. BenzophenoneC. AcetaldehydeD. Acetone and propionic acid |
| Answer» Correct Answer - A::C | |
| 282. |
From amongest the following alcohols, the one that would react fastest with conc. HCl and anhydrous `ZnCl_(2)` isA. 1-ButanolB. 2-ButanolC. 2-Methypropan-2-olD. 2-Methylpropanol |
| Answer» Correct Answer - C | |
| 283. |
Rate of the reaction is fastest when `Z` is - A. ClB. `NH_(2)`C. `OC_(2)H_(5)`D. `OCOCH_(3)` |
| Answer» Correct Answer - A | |
| 284. |
From amongest the following alcohols, the one that would react fastest with conc. HCl and anhydrous `ZnCl_(2)` isA. 1-ButanolB. 2-ButanolC. 2-Methylpropen-2-olD. 2-Methylpropanol |
| Answer» Correct Answer - C | |
| 285. |
The structure of the compound that gives a tribromo derivative on treatment with bromine water is `:`A. B. C. D. |
| Answer» Correct Answer - D | |