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.
| 151. |
Which is the best method the conversion of (A) pentan-2-ol to 3-bromopentane (B) ?A. B. C. (A) `overset(HBr)rarr` (B)D. Both (a) and (b) |
|
Answer» Correct Answer - D Method (c ) would give rearranged product also. It would give a mixture of 2-bromo and 3-bromo and 3-bromo pentane. In methods (a) and (b), no rerrangement occurs and it gives (B) exclusively. The tosyl group, a good leaving group, is then easily displaced by reaction with `Br^(-)` in an `SN^(2)` reaction. |
|
| 152. |
The major organic product in the reaction `CH_(3)-O-CH(CH_(3))_(2)+Hirarr` product isA. `CH_(3)Ooverset(I)overset(|)(C)(CH_(3))_(2)`B. `CH_(3)I+(CH_(3))_(2)CHOH`C. `CH_(3)I+(CH_(3))_(2)CHI`D. `ICH_(2)OCH(CH_(3))_(2)` |
|
Answer» Correct Answer - B `CH_(3)-O-CH(CH_(3))_(2)overset(HI)underset(S_(N)2)rarr CH_(3)I + (CH_(3))_(2)CHOH` |
|
| 153. |
Which of the following statements is not correct ?A. Pentane-`1,5`-diol is soluble while pentan -`1-ol`only slightly soluble in waterB. Cyclohexanol is less soluble in water than henxan -`1-ol`C. Isomeric alcohols have different boiling pointsD. None of these |
|
Answer» Correct Answer - B Cyclohexanol is more soluble in water because the alkyl part in cyclohexanol is more compact than in hexan-1-ol. Thus , its `OH` group is more exposed and available for `H`-bonding with water. In addition, its small compact shape results in fewer water -water `H`-bonds being broken. (1) The additional `OH` group increases the number of `H`-bonds between water and the diol. (3) For example , the decreasing order of boiling point is `CH_(3)(CH_(2))_(3)CH_(2)OHgtCH_(3)underset(OH)underset(|)(CH)overset(CH_(3))overset(|)(CH)CH_(3)gtCH_(3)underset(OH)underset(|)overset(CH_(3))overset(|)(C)CH_(2)CH_(3)` As the branching increases (in isomeric alcohols), the shape becomes more compact and spherical . There is then less surface contact available for van der Waals attractive forces. |
|
| 154. |
Kolbe-schmidt reaction is used forA. Salicylic acidB. SalicylaldehydeC. PhenolD. Hydrocarbon |
| Answer» Correct Answer - A | |
| 155. |
Which of the following is a symmetrical ether?A. `C_(6)H_(5)OCH_(3)`B. `CH_(3)OC_(2)H_(5)`C. `CH_(3)OCH_(3)`D. `CH_(3)CH_(2)CH_(2)OCH_(2)CH_(3)` |
|
Answer» Correct Answer - C In symmetrical ether, both alkyl groups are identical. |
|
| 156. |
Which of the following is a constitutionally symmetrical ether?A. B. C. D. |
|
Answer» Correct Answer - A When the two hydrocarbon group in an ether are idential, the ether is said to be symetrical or simple. When the two hydrocarbon groups are different, the ether is said to be unsymmetrical or mixed. Compound `(1)` is a symmetrical ether as the two alkyl groups bonded to oxygen are the same. `H_(3)C-overset(CH_(3))overset(|)underset(CH_(3))underset(|)(C )-O-overset(CH_(3))overset(|)underset(CH_(3))underset(|)(C )-CH_(3)` Compound `(2)` is an unsymmetrical ether as the alkyl groups bonded to oxygen are different. compound `(3)` is an ester while compound `(4)` is an anhydride. |
|
| 157. |
The `IUPAC` name of the compound isA. `2-(1,1-`dimethylethoxy) propaneB. `1-`isoproxy`-1,1-`dimethyletaneC. `2-`methyl`-2-(1-`methylethoxy) propaneD. `t-`butyl isopropyl ether |
|
Answer» Correct Answer - C The given compound `H_(3)C-overset(._(1)CH_(3))overset(2|)underset(.^(3)CH_(3))underset(|)(C )-O-overset(1)underset(CH_(3))underset(|)(C H)-overset(2)(CH_(3))` The parent chain has three `C` atoms and two substituents: Methyl group at the `2^(nd)C` atom and `OCH(CH_(3))_(2))` also at the `2^(nd)c` atom. option `(4)` is the common name of the given ether. |
|
| 158. |
Phenol can be prepared byA. Hydrolysis of chlorobenzene with aqueous KOH solution.B. Heating sodium salicylate with `(NaOH+CaO)`.C. Reacting cumene hydroperoxide with dil. `H_(2)SO_(4)`.D. Heating benzediaznium chloride with dil. `H_(2)SO_(4)`. |
|
Answer» Correct Answer - B::C::D Reaction (a) is not feasible since the ring is not activated by EWG (e.g., `(NO_(2))` group). So, ArSN reaction is not feasible. |
|
| 159. |
The number of ethers possible with the molecular formula `C_(4)H_(10)O` is.A. threeB. fourC. twoD. one |
|
Answer» Correct Answer - A Ethers have two hydrocarbon groups bonded to an oxygen. They could be symmetrical as well as unsymmetrical: `underset("Methyl n-propyl ether")(CH_(3)-O-CH_(2)CH_(2)CH_(3))` `underset("Isopropyl methyl ether")(CH_(3)-O-underset(CH_(3))underset(|)(CH)-CH_(3))` `underset("Diethyl ehter or ethyl ether")(CH_(3)CH_(2)-O-CH_(2)CH_(3))` With simple ehters teh prefix di is often omitted. |
|
| 160. |
`Th C-O` bonds of saturated aliphatic ehters are formed by the linear orbital overlap of the type:A. `sp^(3)-sp^(2)`B. `sp^(3)-sp^(3)`C. `sp^(2)-sp^(2)`D. `sp^(3)-sp` |
|
Answer» Correct Answer - B In ehters the central oxygen atom (with steric number four) is `sp^(3)` hybridized. In saturated aliphatic ethers, the carbon atoms bonded to the bivalent oxygen are also `sp^(3)` hybridized. Thus `"sigma"` `C-O` bonds are formed by the end to end overlap of `sp^(3)` hybrid orbitals. |
|
| 161. |
Which of the following is the weakest acid?A. PhenolB. `t`-Butyl alcoholC. Ethyl alcoholD. Methyl alcohol |
|
Answer» Correct Answer - B Phenols are stronger acids than monohydric alocohols which have `LIe` the following order of acidic strength on account of electron-releasing nature of alkyl groups: `CH_(3)OH gt RCunderset(1^(@))(H_(2))OH gt R_(2)Cunderset(2^(@))(HOH )gt R_(3)underset(3^(@))(COH)` |
|
| 162. |
The reducing agent used in Bouveault -Blanc reduction isA. `NaBH_(4)`B. `Zn-Cu//C_(2)H_(5)OH`C. `CH_(5)CHO`D. `Na//C_(2)H_(5)OH` |
|
Answer» Correct Answer - D Bouveault -Blanc reduction is carried out by means of excess of sodium and ethanol or `n`-butanol. |
|
| 163. |
Which of the following undergoes exterification with acetic acid at the fastest rate ?A. `(CH_(3))_(2)CHOH`B. `CH_(3)CH_(2)OH`C. `CH_(3)OH`D. `(CH_(3))_(3)COH` |
|
Answer» Correct Answer - C The presence of bulky or large groups near the site of reaction , whether in the alcohol or in the acid, slows down esterification (as well as its reverse hydrolysis). Thus , reactivity in esterification follows the order: `CH_(3)OH gt 1^(@) gt 2^(@) gt 3^(@)` `HCOOH gtCH_(3)COOH gtRCH_(2)COOHgtR_(2)CHCOOHgtR_(3)C COOH` |
|
| 164. |
What are the order of rates of oxidation with `HIO_(4)` of the following diols. Explain with reactions.A. `Me_(2)C(OH)C(OH)Me_(2)`B. `Me_(2)C(OH)CH(OH)Me`C. `CH_(2)(OH)CH_(2)(OH)`D. `MeCH(OH)CH(OH)Me` |
| Answer» altbltdltc (steric factor) | |
| 165. |
p-Nitrophenol is stronger acid than phenol because nitro group is-A. Electron withdrawingB. Electron donatingC. BasicD. Acidic |
|
Answer» Correct Answer - A Electron with drawing `(-m//-R)` nature of `-NO_(2)` group increases acidic nature of p-nitrophenol. |
|
| 166. |
Alkyl chloride is formed when alcohol is treated with HCl in presence of anhydrous `ZnCl_(2)`. The order of reactivity with respect to alcohol isA. `3^(@) gt 2^(@) gt 1^(@)`B. `1^(@) gt 2^(@) gt 3^(@)`C. `2^(@) gt 1^@ gt 3^(@)`D. `1^(@) gt 3^@ gt 2^(@)` |
|
Answer» Correct Answer - A Reactivity order of alcohols with `HCl+ZnCl_(2)("Lucas reagent) is "3^(@)gt2^(@)gt1^(@)`, because stability of carbocation of alcohol is `3^(@) gt 2^(@) gt 1^(@)`. |
|
| 167. |
The number of hydroxy groups in Q is : |
| Answer» Correct Answer - 4 | |
| 168. |
The number of moles of Grignard reagent comsumed per mol of the compound |
| Answer» Correct Answer - 4 | |
| 169. |
Which of the following will get oxidised by `Be_(2)//Koh` into carboxylic acid ?A. `CH_(3)-CH_(2)-OH`B. C. D. |
| Answer» Correct Answer - a,b | |
| 170. |
In the reaction A. B. C. D. |
| Answer» Correct Answer - d | |
| 171. |
Which method is useful for the synthesis of ether?A. B. `C_(2)H_(5)Ona+(CH_(3))_(2)SO_(4) rarr`C. D. `(CH_(3))_(3)CBr+CH_(3)CH_(2)O Na rarr` |
| Answer» Correct Answer - a,b,c | |
| 172. |
The major product in the reaction : A. a hemiacetalB. an acetalC. an etherD. an ester |
| Answer» Correct Answer - b | |
| 173. |
In the following reaction : Compound X is :A. B. C. D. |
| Answer» Correct Answer - c | |
| 174. |
HBr reacts fastest with :A. 2-methylpropan-2-olB. propan-1-olC. propan-2-olD. 2-methhylpropan-1-ol |
| Answer» Correct Answer - a | |
| 175. |
The compound which reacts fastest with Lucas reagent at room temperature isA. butan-1-olB. butan-2-olC. 2-methylpropan-1-olD. 2-methylpropan-2-ol |
| Answer» Correct Answer - d | |
| 176. |
Which of the following compound(s) will give red colour with `FeSO_(4)` + KCNS after keeping open in sunlight for sametime?A. B. C. D. Ph-O-Ph |
| Answer» Correct Answer - a,b | |
| 177. |
Which of the following is not true is case of reaction with heated copper at `300^(@)C`A. Phenol `to` Benzyl alcoholB. Primary alcohol `to` AldehydeC. Secondary alcohol `to `KetoneD. Tertiary alcohol `to `Olefin |
| Answer» Correct Answer - A | |
| 178. |
The correct order of the solubility of the different alcohols in water isA. n-propyl alcohol `gt` ethyl alcohol `gt` n-butyl alcoholB. Ethyl alcohol `gt` n-butyl alcohol `gt` n-propyl alcoholC. n-butyl alcohol `gt` n-propyl alcohol `gt` ethyl alcoholD. Ethanol `gt` n-propanol alcohol `gt` ethyl alcohol |
|
Answer» Correct Answer - A Ethanol `gt` n-propanol `gt` n-butyl alcohol Solubility of alcohols in water decreases as the size of alkyl group of alcohols because tendency to form hydrogen bonding decreases. `underset({:("Isopentyalcohol"),("or 3-methyl butane 2-ol"):})((CH_(3))_(2)underset([D])(CH.CH_(2))CH_(2)OH)` |
|
| 179. |
Which of the following alcohol has highest solubility in waterA. Secondary butyl alcoholB. Tertiary butyl alcoholC. Ethelene glycolD. Glycerol |
|
Answer» Correct Answer - A Higher the number of -OH group Higher the tendency to form inter-H-bonding with water hence higher will be solubility. |
|
| 180. |
In which of the following reactions of alcohol there is no cleavage of C-O bondA. Oxidation reaction of alcoholB. Dehydration reaction of alcoholC. Reduction reaction of alcoholD. Reaction of alcohol with phosphorous tribromide |
|
Answer» Correct Answer - C Oxidation of alcohol does not lead to the cleavage of C-O bond of alcohol. `R-CH_(2)-Ohoverset("pcc")to R-CHO` |
|
| 181. |
The order of stability of carbonium ions isA. Methyl`gt` ethyl `gt` iso-propyl `gt` tert-butylB. Tert-butyl `gt` iso-propyl `gt` ethyl `gt` methylC. Iso-propyl `gt` tert-butyl `gt` ethyl `gt` methylD. Tert-butyl `gt` ethyl `gt` iso-propyl `gt` methyl |
|
Answer» Correct Answer - B `{:(" "CH_(3)),(" "|),(CH_(3)-C^(+) gt CH_(3) -overset(+)(CH)gt CH_(3)overset(+)CH_(2) gt overset(+)CH_(3)),(" "|" "|),(" "CH_(3)" "CH_(3)),(" "3^(@)" "2^(@)" "1^(@) " "{:("Methyl"),("Carbonium ion"):}):}` |
|
| 182. |
Which one of the following reactions would produce secondary alcoholA. `C_(6)H_(5)overset(O)overset(||)C"C"H_(3)`underset(2.H^(+))overset(1.CH_(3)MgBr)to`B. `C_(6)H_(5)overset(O)overset(||)C"C"H_(3)underset(2.H^(+))overset(1.LiA1H_(4))to`C. `CH_(3)CHO underset(2.H^(+))overset(1.LiA1H_(4))to`D. `CH_(3)overset(O)overset(||)C"C"H_(3)underset(2.Br_(2))overset(1.OH^(-))to` |
|
Answer» Correct Answer - B `underset("Acetophenone")(C_(6)H_(5)-overset(O)overset(||)C-CH_(3)overset(LiAIH_(4))to underset(2^(@)"Alcohol")(C_(6)H_(5)-overset(OH)overset(|)CH-CH_(3)` |
|
| 183. |
In which of the following reaction, phenol or sodium phenoxide is not formedA. `C_(6)H_(5)N_(2)Cl+` alco. `KOH to `B. `C_(6)H_(5)Ocl + NaOH to `C. `C_(6)H_(5)N_(2)Cl + ` aq. `NaOH to `D. `C_(6)H_(5)NNCl underset(Delta)overset(H_(2)O)to ` |
| Answer» Correct Answer - B | |
| 184. |
What products are formed when the following compound is treated with `Br_(2)` in the presence of `FeBr_(3)` A. B. C. D. |
|
Answer» Correct Answer - A `-CH_(3)` group is o,p- directing |
|
| 185. |
Phenol isA. A weaker base than `NH_(3)`B. Stronger than carbonic acidC. Weaker than carbonic acidD. A neutral compound |
|
Answer» Correct Answer - C Phenol is weaker acid than carbonic acid `{:(C_(6)H_(5)OH,H_(2)CO_(3),CH_(3)COOH),(K_(a)=10^(-8)-10^(-10),","K_(a)=10^(-7),","K_(a)=10^(-5)):}` |
|
| 186. |
Which of the following willnot be solube in sodium hydrogen carbonateA. o-NitrophenolB. Benzenesulphonic acidC. 2,4,6-trinitrophenolD. Benzoic acid |
|
Answer» Correct Answer - A o-nitrophenol is weaker acid than `HCO_(3)^(-)` |
|
| 187. |
Which of the following compounds shows evidence of the strongest hydrogen bondingA. Propane-1-olB. Propane-2-olC. Propane-1,2-diolD. Propane-1,2,3-triol |
|
Answer» Correct Answer - D Propane-1,2,3-triol or glycerol has very high boiling point i.e., `290^(@)C` , The high viscosity and high boiling point of glycerol are due to association of glycerol molecules through extensive intermolecular hydrogen bonding due to presence of three polar -OH group |
|
| 188. |
Which statement is incorrectA. Phenol is a weak acidB. Phenol is an aromatic compoundC. Phenol liberates `CO_(2)` from `Na_(2)CO_(3)` solutionD. Phenol is soluble in NaOH |
|
Answer» Correct Answer - C Phenol is not sufficiently acidic to liberate `CO_(2)` from `Na_(2)CO_(3)` solution. |
|
| 189. |
`Ph-overset(O)overset(||)(C)-O-H+CH_(3)-O^(18)-H overset(H^(+))(hArr) (X)+H_(2)O`, Identify X,A. `X =Ph-overset(O)overset(||)(C)-O^(18)-CH_(3)` (Trans esterification)B. `X=Ph -overset(O)overset(||)(C)-O^(18)-CH_(3)` (Esterification reaction)C. `X = Ph-overset(O)overset(||)(C)-O^(18)-CH_(3)` (Saponification)D. `X=Ph-overset(O)overset(||)(C)--CH_(3)` (Hydrolysis) |
|
Answer» Correct Answer - B `underset("(acid)")(Ph-overset(O)overset(||)(C)-O-H) + underset("(alcohol)")(CH_(3)-overset(18)(O)-H) overset(H^(o+))(hArr) underset("(ester)")(Ph-overset(O)overset(||)(C)-overset(18)(O)-CH_(3))` |
|
| 190. |
Fastest rate of reaction will be when R is :A. `CH_(3) -`B. `CH_(2) - CH_(2)`C. `CH_(3) - underset(CH_(3))underset(|)(CH)-`D. `CH_(3)-underset(CH_(3))underset(|)overset(CH_(3))overset(|)(C)-` |
|
Answer» Correct Answer - A Alcohol shows acidic behavior in eaterification, so `CH_(3)OH` is most acidic among all the option, so rate of esterification will be maximum. |
|
| 191. |
Iodoform can be obtained on warming `NaOH` and iodine with :A. `CH_(3)CH_(2)CH(OH)CH_(3)`B. `(CH_(3))_(2)CH overset(O)overset(||)(C)C_(2)H_(5)`C. `CH_(3)-underset(O)underset(||)(C)-OCH_(3)`D. `(CH_(3))_(2)CHCH_(2)OH` |
|
Answer» Correct Answer - A 2- Butanol |
|
| 192. |
Assertion : The ease of dehydration of the following alcohols is Reason : Alcohols leading to conjugated alkenes are dehydrated to a greater extent.A. if both assertion and reason are true and the reason is the correct explanation of the assertionB. If both assertion and reason are true but reason is not the correct explanation of the assertion.C. If assertion is true but reason is falseD. If the assertion and reason both are false |
|
Answer» Correct Answer - A Alcohols have higher boiling points than ethers due to intermolecular H-bonding is present in alcohols and not in ethers. |
|
| 193. |
Propene is the product obtained by dehydration ofA. 2-propanolB. 1-propanolC. PropanalD. n-propyl alcohol |
| Answer» Correct Answer - A | |
| 194. |
Ethylene may be obtained by dehydration of which of the following with concentrated `H_(2)SO_(4)` at `160-170^(@)C`A. `C_(2)H_(5)OH`B. `CH_(3)OH`C. `CH_(3)CH_(2)CH_(2)OH`D. `(CH_(3))_(2)CHCH_(2)OH` |
| Answer» Correct Answer - A | |
| 195. |
The alcohol which does not give a stable compound on dehydration isA. Ethyl alcoholB. Methyl alcoholC. n-propyl alcoholD. n-butyl alcohol |
| Answer» Correct Answer - B | |
| 196. |
Which of the following statement is correct regarding case of dehydration in alcoholsA. Primary `gt` SecondaryB. Secondary `gt` TertiaryC. Tertiary `gt` PrimaryD. None of these |
|
Answer» Correct Answer - C Correct order of dehydration in alcohols `3^(@) gt 2^(@) gt 1^(@)`. |
|
| 197. |
Which of the following would undergo dehydration most readilyA. 1-phenyl-1 butanolB. 2-phenyl-2 butanolC. 1-phenyl-2 butanolD. 2-phenyl-1-butanol |
| Answer» Correct Answer - C | |
| 198. |
In `CH_(3)CH_(2)OH`, the bond that undergoes heterolytic cleavage most readily isA. C-CB. C-OC. C-HD. O-H |
|
Answer» Correct Answer - D `CH_(3)CH_(2)OH underset("bond fusion")overset("heterolytic")to CH_(3)CH_(2)O^(-)+H^(+)` |
|
| 199. |
Isoprophyl alcohol on oxidation formsA. AcetoneB. EtherC. EthyleneD. Acetaldehyde |
|
Answer» Correct Answer - A `CH_(3)-underset(OH)underset(|)CH-CH_(3)underset(KMnO_(4))overset("Oxidation")to underset("Acetone")(CH_(3)-underset(O)underset(||)C-CH_(3))` |
|
| 200. |
Read the following statements carefully (A) A secondary alcohol on oxidation gives a ketone (B) Ethanol reacts with conc. `H_(2)SO_(4)` at `180^(@)C` to yield ethylene (C) Methanol reacts with iodine and sodium hydroxide to given a yellow precipitate of iodoform (D) Hydrogen gas is liberated when sodium is added to alcohol. Select the correct statements from the above setA. A,BB. C,DC. A,B,DD. A,C,D |
|
Answer» Correct Answer - B (a) `CH_(3)-underset(OH)underset(|)CH-CH_(3)overset("Oxidation")to CH_(3)-underset(O)underset(||)C-CH_(3)` `(b) CH_(3)-CH_(2)-OH underset(180^(@)C)overset("Conc." H_(2)SO_(4))to CH_(2)=CH_(2)+H_(2)O` (d) `2CH_(3)CH_(2)OH + 2Na to 2CH_(3)-CH_(3)-CH_(2)-ONa +H_(2)` |
|