CBSE Questions for Class 12 Engineering Chemistry Alcohols,Phenols And Ethers Quiz 5 - MCQExams.com

Among the following compounds, the one which can be dehydrated most easily is:
  • $$CH_{ 3 }-CH_{ 2 }-\overset { \overset { CH_{ 3 } }{ | }  }{ \underset { \underset { OH }{ | }  }{ C }  }-CH_{ 2 }CH_{ 3 }$$
  • $$CH_3-CH_2-CH_2-\underset { \underset { OH }{ | }  }{ C } H-CH_3$$
  • $$CH_3-CH_2-CH_2-CH_2-CH_2-OH$$
  • $$(CH_3)_2CH-CH_2-CH(OH)-CH_3$$
product A is:
791690_07c3c1e295974c05985e657937996da7.png
  • all
Which of the following phenols has lowest solubility in water?
  • Phenol
  • o-Nitrophenol
  • m-Nitrophenol
  • p-Nitrophenol
An Alcohol X pass over Cu at 300C, then produced compound decolourised Bromine liquid, X is:
(A) $$CH_3-\underset{\underset{\,\,\,\,CH_3}{|}}CH-CH_2-CH_2-OH$$
(B) $$CH_3-\overset { \underset { | }{ \, \, \, \, \,  OH }  }{ \underset { \overset { | }{ \, \, \, \, \, CH_{ 3 } }  }{ C }  }-CH_2-CH_3 $$
(C) $$CH_3\overset{\overset{CH_3}{|\,\,\,\,\,}}{CH}-\overset{\overset{OH}{|\,\,\,}}{CH}-CH_3$$
The order of given alkanols $$A,B,C$$  in their reactivity towards acid catalysed dehydration is:
  • $$A> B> C$$
  • $$B> A> C$$
  • $$B> C> A$$
  • $$C> B> A$$
Dehydration of the following in increasing order is:
773158_f790ce03ae684e8281261acd5bc9dc0a.png
  • $$I < II < III < IV$$
  • $$II < III < IV < I$$
  • $$I < III < II < IV$$
  • $$I < IV < II < III$$
Diols (I - IV) which react with $$CrO_{3}$$ in aqueous $$H_{2}SO_{4}$$ and yield products that readily undergo decarboxylation on heating are:
878147_ce2bb754f6ae48229fdcc87784d2da74.png
  • I and II
  • II and III
  • II and IV
  • I and IV
 Which of the following statements is incorrect regarding preparation of alcohols?
  • Aldehydes and Ketones on catalytic reduction by [H] give primary alcohol and secondary alcohol respectively
  •  Ketones on reaction with Grignard’s reagent gives tertiary alcohol
  • Aldehydes on reaction with Grignard’s reagent gives primary or secondary alcohol
  • Alkyl halides on reaction alcoholic potash gives alcohol
Rate of dehydration when given compound is treated with conc, $${ H }_{ 2 }{ SO }_{ 4 }$$.
875025_4d67cb67323e4ccda902154718352f97.png
  • P > Q > R > S
  • Q > P > R > S
  • R > Q > P > S
  • R > Q > S > P
The correct decreasing order of dehydration of following alcohols with conc. $$H_2SO_4$$ is:
874563_a300cdb3823d4346b9f6d9539a0a0279.png
  • C > A > B > D
  • D > A > C > B
  • A > B > C > D
  • D > C > A > B
Methylphenyl ether can be obtained by reacting :
  • phenolate ions and methyl iodide
  • methoxide ions and bromobenzene
  • methanol and phenol
  • bromo benzene and methyl bromide
Correct representation of 3- methylpent-3-en-2-ol is :
Which of the following compounds is stable?
  • $$CH_3CH(OH)_2$$
  • $$(CH_3)_2CH(OH)_2$$
  • $$CCl_3CH(OH)_2$$
  • None of these
Which of the following is best method to prepare phenyl-t-butyl ether?
  • $$(CH_{3})_{3}C - O^{-}Na^{+} + C_{6}H_{5}Br$$
  • $$C_{6}H_{5}ONa + (CH_{3})_{3}CCl$$
  • $$(CH_{3})_{2}C = CH_{2}\xrightarrow[C_6H_5OH]{Hg(OCOCH_3)_{2}} \overset{NaBH_4}{\rightarrow}$$
  • None of these
Product of the above reaction is:
880766_d49079fa543141cf9db89bc84b6abc2f.png
A hydrocarbon $$'A' (C_{3}H_{8})$$ on treatment with chlorine in presence of sunlight yielded compound $$'B'$$ as the major product. Reaction of $$'B'$$ with aqueous $$KOH$$ gave $$'C'$$ which on treatment with concentrated $$H_{2}SO_{4}$$ yielded $$'D'$$. Hydrogenation of $$'D'$$ gave back $$'A'$$. The sequence of reactions involved in the above conversion is:
  • Substitution, Substitution, Addition, Dehydration
  • Substitution, Substitution, Dehydration, Addition
  • Substitution, Dehydration, Addition, Addition
  • Addition, Substitution, Dehydration, Substitution
Ethyl alcohol obtained by fermentation of starch or molasses is called wash, and what is it’s purity?
  • 15%
  • 45%
  • 55%
  • 35%
The correct IUPAC name of the compound is ?
928651_dfd29716a25f4b6192decc669a22230b.png
  • 2-ethyl-1-chlorocyclohexanol
  • 4-chloro-5-ethylcyclhexanol
  • 4-hydroxy-2-ethyl-1-chlorocycloheane
  • 4chloro-3-ethylcyclohexanol
Which of the following alcohol will have the fastest rate of dehydration ?
An alkene $$CH_3CH = CH_2$$ is treated with $$B_2H_6$$ in presence of $$H_2O_2$$. The final product formed is:
  • $$CH_3CH_2CHO$$
  • $$CH_3CH(OH)CH_3$$
  • $$CH_3CH_2CH_2OH$$
  • $$(CH_3CH_2CH_2)_3B$$
Which of the following statements is not correctly showing the trend of the properties mentioned ?
  • $$CH_3CH_2OH > CH_3CH_2CH_2OH > \underset {(Solubility)}{CH_3CH_2CH_2CH_2OH}$$
  • $$CH_3CH_2OH > CH_3CH_2CH_2OH > \underset {(Boiling point)}{CH_3CH_2CH_2CH_2OH}$$
  • $$CH_3CH_2CH_2OH > CH_3{\underset{CH_3}{\underset{|}{CH}}}-CH_2OH >\underset{Boiling \, point}{CH_3-\underset{CH_3}{\underset{|}{\overset{CH_3}{\overset{|}C}}}-OH}$$
  • $$CH_3-{\underset{CH_3}{\underset{|}{\overset{CH_3}{\overset{|}{C}}}}}-OH$$<$$CH_3{\underset{CH_3}{\underset{|}{CH}}}-CH_2OH$$ <$$CH_3CH_2CH_CH_2OH$$
A compound $$C_6H_{14}O_2$$ has two tertiary alcoholic groups. The IUPAC name of compound is:
  • 2,3 - dimethyl - 1,2 - butanediol
  • 3,3 - dimethyl - 1,2 - butanediol
  • 2,3 - dimethyl - 2,3 - butanediol
  • 2 - methyl - 2,3 - pentanediol
Strength of acidity is in order :
936112_153d3899d7af437ab6a4615b0b5cb266.png
  • $$II > I $$
  • $$I > II$$
  • $$I=II$$
  • cannot be determined
The best method to prepare 3-methylbutan-2-ol from 3-methylbut-1-ene is:
  • addition of water in presence of dil. $$H_2SO_4$$
  • addition of $$HCI$$ followed by reaction with dil. $$NaOH$$
  • hydroboration - oxidation reaction
  • Reimer - Tiemann reaction.
Primary, secondary and tertiary alcohols can be distinguish by:
  • Baeyer's reagent
  • Fehling's solution
  • Sulphuric acid
  • Lucas reagent
The decreasing order of boiling points of the following alcohols is?
  • 3-methylbutan-2-ol > 2-methylbutan-2-ol > pentan-1-ol
  • pentan-1-ol > 3-methylbutan-2-ol > 2-methylbutan-2-ol
  • 2-methylbutan-2-ol > 3-methylbutan-2-ol > pentan-1-ol
  • 2-methylbutan-2-ol > pentan-1-ol >3-methylbutan-2-ol
Alcohols of low molecular weight are:
  • soluble in water
  • soluble in water on heating
  • insoluble in water
  • insoluble in all solvents.
Which of the following synthesis given $$3$$-methyl-$$1$$-hexanol?
  • $$2-Bromohexane \xrightarrow[dry \, ether]{Mg} \,\, \xrightarrow[(ii) H_3 O^+]{(i) HCHO}$$
  • $$3-Bromopentane \xrightarrow[dry \, ether]{Mg} \,\, \xrightarrow[(ii) H_3O^+]{(i) CH_3 CHO}$$
  • $$1 - Bromobutane \xrightarrow[dry \, ether]{Mg} \,\, \xrightarrow[(ii) H_3 O^+]{(i) CH_3 COCH_3}$$
IUPAC name of $$CH_3CH_2CH_2{\underset {CH_2OH}{\underset{|}{CH}}}-CH_2CH_3$$ is:
  • 3 -propylbutan-1-ol
  • 2-Ethylpentan - 1 - ol
  • 3- methyl hydroxyhexane
  • 2- ethyl -2 - propyl ethanol
Vapours of an alcohol X when passed over hot reduced copper, produce an alkene, the alcohol is:
  • primary alcohol
  • secondary alcohol
  • tertiary alcohol
  • dihydric alcohol
Arrange the following alcohols in order of increasing reactivity towards sodium metal.
(i) $$(CH_3)_3C-OH$$ (ii) $$(CH_3)2CH - OH$$ (iii) $$CH_3CH_2OH$$
  • (iii) < (ii) < (i)
  • (ii) < (i) < (iii)
  • (i) < (ii) < (iii)
  • (iii) < (i) < (ii)
Arrange the following compounds in increasing order of boiling points . Propan-1-ol , butan-1-ol , butan-2-ol, pentan-1-ol.
  • Propan-1-ol, butan-2-ol,butan-1-ol ,pentan-1-ol
  • Propan-1-ol, butan-1-ol,butan-2-ol ,pentan-1-ol
  • Pentan-1-ol , butan-2-ol , butan-1-ol , propan -1-ol
  • Pentan-1-ol , butan-1-ol , butan-2-ol , propan -1-ol
Which of the following compounds does not react with $$NaOH$$?
  • $$CH_3COOH$$
  • $$CH_3CONH_2$$
  • $$C_6H_5OH$$
  • $$CH_3CH_2OH$$
Which of the following alcohols will give the most stable carbocation during dehydration?
  • 2-Methyl -1- propanol
  • 2-Methyl -2- propanol
  • 1-Butanol
  • 2-Butanol
$$(CH_3)_3C - CH_2OH\xrightarrow[170^0C]{Conc.H_2SO_4}$$ X
In the reaction , X is:
  • $$(CH_3)_2C = CHCH_3$$
  • $$(CH_3)_{2}C = CH_{2}$$
  • $$(CH_3)_2CHCH_2CH_3$$
  • $$CH_3-CH_2-\underset{CH_3}{\underset{|}C}=CH_2$$
Unlike phenol, 2,4-dinitrophenol is soluble in sodium carbonate solution in water because ?
  • presence of two - $$NO_2$$ groups in the ring makes 2 , 4 - dinitrophenol a stronger acid than phenol.
  • presence of two - $$NO_2$$ groups in the ring makes 2 , 4 - dinitrophenol a weaker acid than phenol.
  • presence of two $$-NO_2$$ groups make the hydrogen bonding easier, making 2 , 4-dinitrophenol soluble.
  • nitro group reacts with $$Na_2CO_3$$ while -$$OH$$ group does not.
Which of the following alcohols is dehydrated most easily with conc. $$H_2SO_4$$ ?
  • $$p-O_2NC_6H_4CH(OH)CH_3$$
  • $$p-ClC_6H_4CH(OH)CH_3$$
  • $$p-CH_3OC_6H_4CH(OH)CH_3$$
  • $$C_3H_5CH(OH)CH_3$$
An alcohol X on heating with concentrated $$H_2SO_4$$ gives an alkene Y which can show geometrical isomerism.The alcohol X is?
  • $$CH_3CH_2OCH_3$$
  • $$CH_3CH_2CHO$$
  • $$CH_3CH_2CH_2OH$$
  • $$CH_3CH_2CH(OH)CH_3$$
Methyl alcohol is industrially prepared by the action of ?
  • $$CH_3COCH_3$$
  • $$CO + H_2$$
  • $$CH_3COOH $$
  • $$C_2H_5OH$$
Give IUPAC name of the compound given below :
$$CH_3-\underset{Cl}{\underset{|}C}H-CH_2-CH_2-\underset{OH}{\underset{|}C}H-CH_3$$
  • 2- Chloro - 5 - hydroxyhexane
  • 2 - Hydroxy - 5 - chlorohexane
  • 5 - Chlorohexan - 2 - ol
  • 2 - Chlorohexan - 5 - ol
Which compound is the most soluble in water?
  • Chloroethane
  • Ethanol
  • Ethanal
  • Ethylene glycol
Which of the following alcohols is the least soluble in water?
  • Ethanol
  • 1-Propanol
  • 1-Butanol
  • 1-Pentanol
The order of reactivity of following alcohols with halogen acids is ______
(I) $$CH_3CH_2 - CH_2-OH$$ 

(II) $$CH_3CH_2-(CH_3)CH-OH$$

(III) $$CH_3CH_2 - {\underset{CH_3}{\underset{|}{\overset{CH_3}{\overset{|}{C}}}}}-OH$$
  • (I) > (II) > (III)
  • (III) > (II) > (I)
  • (II) > (I) > (III)
  • (I) > (III) > (II)
The general formula for alcohol series is $$C_nH_{2n+1}OH$$. Which is the formula for alcohol contains four carbon?  
  • $$C_5H_{11}OH$$
  • $$C_4H_{9}OH$$
  • $$C_4H_{8}OH$$
  • $$C_3H_{8}OH$$
Compound $$C_2H_6O$$ has two isomers X and Y. On reaction with $$HI$$, X gives alkyl iodide and water while Y gives alkyl iodide and alcohol.Compounds X and Y are respectively :
  • $$C_2H_5OC_2H_5\, and \,CH_3OC_2H_5$$
  • $$CH_3OCH_3 \,and \,C_2H_5OCH_3$$
  • $$C_2H_5OH \,and \, CH_3OCH_3$$
  • $$CH_3OH \,and \, CH_3OCH_3$$
Ether is obtained from ethyl alcohol in presence of $$H_2SO_4$$ at?
  • 113 K
  • 443 K
  • 413 K
  • 213 K
Diethyl ether when refluxed with excess of HI gives two molecules of (i). Ethers can be most commonly prepared by reaction of (ii) and (iii) . The method is called (iv).
(i), (ii),(iii) and (iv) respectively are?
  • ethyl iodide, sodium alkoxide , alkyl halide, Williamson's synthesis
  • ethanol, alcohol , alkyl halide , substitution
  • methyl iodide, Grignard's reagent , alkyl halide , Williamson's synthesis
  • ethyl iodide, phenol, ethyl iodide, esterification
The major product formed during the reaction of 1- methyl cyclopentene with $$CH_3CO_3H$$ is:
Cis-3-hexene $$\xrightarrow{(a)}$$ meso 3,4-hexanediol
trans-3-hexene $$\xrightarrow{(b)}$$ meso 3,4-hexanediol.
Choose pair of reagent (a, b) for above conversions.
  • Cold $$KMnO_4, OsO_4$$
  • Cold $$KMnO_4, RCO_3H/H_3O^\bigoplus$$
  • $$RCO_3H/H_3O^\bigoplus, \, cold \, KMnO_4$$
  • None of these
Reaction of $$R-2-$$butanol with $$p-$$toluenesulphonyl chloride in pyridine followed by reaction with $$LiBr$$ gives:
  • $$R-1-$$butyl bromide
  • $$R-2-$$butyl tosylare
  • $$R-1-$$butyl tosylate
  • $$R-2-$$butyl bromide
0:0:1


Answered Not Answered Not Visited Correct : 0 Incorrect : 0

Practice Class 12 Engineering Chemistry Quiz Questions and Answers