CBSE Questions for Class 12 Medical Chemistry Alcohols, Phenols And Ethers Quiz 11 - MCQExams.com

Which of the following statements is/are true about phenol?
  • It is a stronger acid than water
  • It forms salt with $$NaHCO_3$$
  • Passing $$CO_2$$ through an aqueous solution of sodium phenoxide gives phenol
  • On exposure to air, it turns pink in colour
Select schemes A, B, C out of the given below.
I. Acid catalysed hydration  
II. Hydroboration oxidation
III. Oxymecruation-demercuration

124170.png
  • I in all cases
  • I, II, III
  • II, III, I
  • III, I, II
Primary alcohols can be prepared from alkenes by:
  • mercuration and demercuration of alkenes
  • direct hydration of alkenes
  • hydroboration of alkenes
  • all of the above
What is $$A$$ ?

205850.png
  • $$ TsO-CH_2 - C \equiv CH$$
  • $$ TsO_2-CH_2 - C \equiv CH$$
  • $$ TsO-CH_2 - C - CH_3$$
  • none of the above
How many pi($$\pi $$) electron are there in the following molecule?
1346601_c585aff6cfbf4f5c8fe1a0a6672adec9.png
  • $$4$$
  • $$6$$
  • $$8$$
  • $$10$$
Reactions I and II are limited mainly to naphthalene compounds. These reactions are called, respectively:
247470_620943915daa431c89d0e79affc2d8dd.png
  • bucherer reaction and its reversal
  • bischler-Napieralski reaction and its reversal
  • birnbaum-Simonini reaction and its reversal
  • borodine-Hunsdiecker reaction and its reversal
Which of the following statements is/are correct?
247363.bmp
  • The compounds (B) is (I).
  • The compounds (B) is (II)
  • The compounds (C) is (I)
  • The compounds (C) is (II)
The compound (A) is:
249321_3644845d0e0043c79481076ed30ec119.png
Which statement is correct for the conversion of $$ROH$$ to $$RX$$ by reagents $$(A)$$ $$ ( SOCl_{2},\ PBr_{3}$$ $$ PCl_{3}$$ $$ Pl_{3},\:TsCl  )$$ compared to using $$HX$$?
  • No rearrangement occurs with predictable stereochemistry by reagents $$(A)$$
  • Reasgents $$(A)$$ are not useful for $$\displaystyle 3^{\circ}$$ alcohols, while $$HX$$ reacts easily with $$\displaystyle 3^{\circ}$$ alcohols involving no rearrangement.
  • Reagents $$(A)$$ must be used in anhydrous conditions because all react vigorously with $$\displaystyle H_{2}O$$ and they produce harmful gases $$\displaystyle \left ( SO_{2},HCl,HBr,\:and\:HI \right )$$
  • All of the above
 In given reaction  A is :
146711_e37c675569a34f3280650c9470a92446.png
Which is the best method for the conversion of (A) $$pentan-3-ol\ to\ 3-bromopentane$$ (B)?

  • $$\displaystyle \left ( A \right )\xrightarrow {HBr}\left ( B \right )$$
  • None of these
Consider the following reaction sequence.
$$\displaystyle { CH }_{ 2 }={ CH }_{ 2 }\xrightarrow [ dil.{ KMnO }_{ 4 } ]{ cold } A\xrightarrow [ { PCl }_{ 5 } ]{ excess } B$$

The products $$(A)$$ and $$(B)$$ are, respectively:
  • $$\displaystyle { CH }_{ 3 }{ CH }_{ 2 }OH$$ and $$\displaystyle { CH }_{ 3 }{ CH }_{ 2 }Cl$$
  • $$\displaystyle { CH }_{ 3 }{ CHO }$$ and $$\displaystyle { CH }_{ 3 }{ CHCl }_{ 2 }$$
  • $$\displaystyle { CH }_{ 2 }OH { CH }_{ 2 }OH$$ and $$\displaystyle { CH }_{ 2 }Cl{ CH }_{ 2 }Cl$$
  • $$\displaystyle { CH }_{ 2 }OH{ CH }_{ 2 }OH$$ and $$\displaystyle { CH }_{ 2 }OH{ CH }_{ 2 }Cl$$

251495.png
  • Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
  • Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
  • Assertion is correct but Reason is incorrect
  • Both Assertion and Reason are incorrect
The product (B) is :

249658_01ff5e1ec5f04b53a5a9a3c7b38af82b.png
  • All
For the reaction given, what is product $$(A)$$?
253318_521e595ebd4148ba974f4ec440b7708a.png
Which statement is correct for the conversion of ROH to RX by reagents $$\displaystyle \left ( SOCl_{2},PBr_{3},PCl_{3},PI_{3} \right )$$  and TsCl compared to using HX?
  • No rearrangement occurs with predictable stereo-chemistry by reagents
  • Reagents are not useful for $$\displaystyle 3^{\circ}$$ alcohols, while HX reacts easily with $$\displaystyle 3^{\circ}$$ alcohols involving no rearrangement
  • Reagents must be used in anhydrous conditions because all react vigrously with $$\displaystyle H_{2}O$$ and they produce harmful gases ($$\displaystyle SO_{2}$$, HCl, HBr, and HI)
  • All
When benzene sulphonic acid and p-nitrophenol are treated with $$NaH{CO}_{3}$$, the gases released respectively :
  • $${SO}_{2},{NO}_{2}$$
  • $${SO}_{2},NO$$
  • $${SO}_{2}, {CO}_{2}$$
  • $${CO}_{2}, {CO}_{2}$$
The product (B) is:

249652_99b8dffffd3140a3aa5294dccd4569db.png
  • all
Consider the reaction:

 $$\displaystyle C_{3}H_{7}-OH+Et{O^{\bigoplus }}BF_{4}^{\circleddash }\rightarrow C_{3}H_{7}-O-Et+EtOEt$$. 

Which of the following statements is wrong?
  • The nucleophile in the reaction is $$\displaystyle C_{3}H_{7}O^-$$
  • The nucleophile in the reaction is $$\displaystyle BF_{4}^{{\circleddash }}$$
  • The leaving group is $$\displaystyle Et_{2}O$$
  • $$\displaystyle SN^{2}$$ reaction occurs
Phenol is an organic compound even though it is soluble in water due to the presence of:
  • ionic bonding
  • covalent bonding
  • hydrogen bonding
  • coordinate bonding
Correct statement(s) in case of n-butanol and t-butanol is (are):
  • both are having equal solubility in water.
  • t-butanol is more soluble in water than n-butanol.
  • boiling point of t-butanol is lower than n-butanol.
  • boiling point of n-butanol is lower than t-butanol.
Give the decreasing order of reactivity of the following compounds with $$HBr$$.

249648_2ead6a661a6041dbb0e7cd272bb4f9bd.png
  • III > IV > II > I
  • III > II > IV > I
  • III> II > I > IV
  • II > III > IV > I
A compound (X) reacts with thionyl chloride to give a compound (Y). (Y) reacts with $$\displaystyle Mg$$ to form a Grignard reagent, which is treated with acetone and the product is hydrolysed to give 2-methyl-2- butanol. What are structural formulae of (X) and (Y) ?
  • X = Acetic acid Y = Ethyl Chloride
  • X = Acetaldehyde Y = Ethyl Chloride
  • X = Ethyl Alcohol Y = Ethyl Chloride
  • X = Propyl alcohol Y = Propyl Chloride
Select the incorrect synthesis.
In which of the following solvents, KI has highest solubility? The dielectric constant $$(\epsilon)$$ of each liquid is given in parentheses.
  • $$ C_{6}H_{6}(\epsilon =0)$$
  • $$(CH_{3})_{2}CO(\epsilon =21)$$
  • $$CH_{3}OH(\epsilon =32)$$
  • $$CCl_{4}(\epsilon =0)$$
For the reaction the major product is:

274431.png
The boiling point of phenols are higher than the hydrocarbons of comparable masses due to:
  • more polarising power
  • presence of hydrogen bonding
  • resonance stabilisation
  • acidic character
$$PhCH=C{ H }_{ 2 }\overset { ArC{ O }_{ 3 }H }{ \underset { C{ H }_{ 2 }{ Cl }_{ 2 } }{ \longrightarrow  }  } A\overset { 1.LiAl{ H }_{ 4 }\cdot { Et }_{ 2 }O }{ \underset { 2.{ H }_{ 2 }O }{ \longrightarrow  }  } B$$
The end product (B) is :
  • $$PhCH(OH)C{ H }_{ 3 }$$
  • $$PhC{ H }_{ 2 }C{ H }_{ 2 }COAr$$
  • $$PhC{ H }_{ 2 }C{ H }_{ 2 }OH$$
Propene is allowed to react with m-chloroperoxybenzoic acid. The product (A) is then reduced with $$\displaystyle { LiAlH }_{ 4 }$$ in dry ether to give (B).

$$\displaystyle { CH }_{ 3 }CH={ CH }_{ 2 }\xrightarrow { m-CPBA }\    A\xrightarrow [ 2.{ H }_{ 3 }{ O }^{ + } ]{ 1.{ LiAlH }_{ 4 } } B$$

The structure of the product (B) is:
  • $$\displaystyle { CH }_{ 3 }{ CH(OH)CH }_{ 2 }OH$$
  • $$\displaystyle { CH }_{ 3 }{ CH }_{ 2 }{ CH }_{ 2 }OH$$
  • $$\displaystyle { CH }_{ 3 }{ CH }(OH)CH_{ 3 }$$
Tertiary alcohols are more acidic than phenol.
  • True
  • False
Complete the blanks by identifying $$X$$ and $$Y$$.
399096_eb04222c956244ec8a6cd2961faf5cba.png
  • Ethanal, ethene
  • Ethanol, ethene
  • Ethanal, ethyne
  • Ethanol, ethyne
Identify the correct sequence of given steps for the conversion of calcium carbide to methyl alcohol.
(a) Reaction with aqueous $$KOH$$
(b) Hydrolysis
(c) Reaction with soda lime
(d) Reaction with $$Ha{SO}_{4}/{H}_{2}{SO}_{4}$$
(e) Reaction with $$Hg{SO}_{4}$$
(f) Reaction with $$P{Cl}_{5}$$
  • $$b\ d\ e\ c\ f\ a$$
  • $$b\ d\ c\ a\ f\ e$$
  • $$b\ f\ d\ e\ a\ c$$
  • $$d\ b\ c\ e\ f \ a$$
Ethanol is produced by/from :
  • ethene
  • fermentation of sugars
  • both A and B
  • none of the above

What will be product in given reaction?
1055138_3056a32169e745c89e9f204470f51372.png
Which has the smallest size ?
  • $$Na^+$$
  • $$Mg^{2+}$$
  • $$Al^{3+}$$
  • $$P^{5+}$$
$$R-OH\xrightarrow{PBr_3}A\xrightarrow[]{Mg/Dry \ ether}B\xrightarrow[]{HCHO}C\xrightarrow[]{H^+/H_2O}D$$

What are $$A,B,C$$ & $$D$$ respectively?
  • $$R-Br,R-Br-Mg,R-CH_2Mg-Br,R-CH_2CHO$$
  • $$R-Br,R-Mg-Br,R-CH_2-O-Mg-Br,R-CH_2CHO$$
  • $$R-Br,R-Mg-Br,R-CH_2-O-Mg-Br,R-CH_2OH$$
  • $$R-Br,R-Mg-Br,R-CH_2-Br,R-CH_2OH$$
Identify E:
522770_3288490e866a49688f27f9e25bd4f4dd.png
  • ethene
  • ethane
  • ethyne
  • propyne
Which one of the following is produced when acetone is saturated with $$HCl$$ gas?
  • Acetone alcohol
  • Phorone
  • Mesityl oxide
  • Benzene
$$CH_3CH_2-OH\xrightarrow{A}CH_3-CH_2-Cl\xrightarrow{B}CH_2=CH_2.$$

 A and B in this sequence of reactions are :
  • KOH(aq) and $$PCl_5$$
  • $$PCl_5$$ and KOH(aq)
  • $$Cl_2$$ and KOH(alc)
  • $$PCl_5$$ and KOH(alc)
$$R-OH\xrightarrow {P+I_2}A\xrightarrow[alc. \ KCN]{Heating}B\xrightarrow[Na/alcohol]{LiAlH_4}C\xrightarrow[NaNO_2+dil\  HCl]{HNO_2}D$$

What are $$A,B,C$$ & $$D$$ respectively?
  • $$R-I$$, $$R-CN$$, $$R-NH_2$$, $$R-CH_2OH$$
  • $$R-I$$, $$R-CN$$, $$R-CH_2-NH_2$$, $$R-CH_2OH$$
  • $$R-I$$, $$R-NC$$, $$R-CH_2-NH_2$$, $$R-CH_2OH$$
  • $$R-I$$, $$R-CN$$, $$R-CH_2-NO_2$$, $$R-CH_2OH$$
$$R-OH\xrightarrow {PBr_3}A\xrightarrow[]{Mg/Dry \ ether}B\xrightarrow[CH_2-CH_2-O]{Grignard\ reaction}C\xrightarrow[]{H^+/H_2O}D$$

What are $$A,B,C$$ and $$D$$ are respectively?
  • $$R-Br,R-Mg-Br,R-CH_2-O-Mg-Br,R-CH_2CH_2-OH$$
  • $$R-Br,R-Mg-Br,R-CH_2-O-CH_2-Mg-Br,R-CH_2CH_2-OH$$
  • $$R-Br,R-Mg-Br,R-CH_2-CH_2-O-Mg-Br,R-CH_2CH_2-OH$$
  • $$R-Br,R-Mg-Br,R-CH_2-CH_2-O-Mg-Br,R-CH_2OH$$
$$CH_3-OH\xrightarrow{P+I_2}A\xrightarrow[alc\ KCN]{Heating}B\xrightarrow[Na/alcohol]{LiAlH_4}C\xrightarrow[NaNO_2\ + \ dil \ HCl] {HNO_2}D$$

What is $$D$$?
  • $$CH_3CHO$$
  • $$CH_3COOH$$
  • $$CH_3CH_2OH$$
  • $$CH_3-O-CH_3$$
Product formed in the following reaction is/are :
617487_1ad581e575ab4283aa3b736d82cf6b6d.png
  • both (A) and (B)
  • none is correct
Under suitable condition temperature,pressure and catalyst,methanol can be obtain by:
  • partial oxidation of hydrocarbons
  • reacting $$H_2$$ with $$CO$$
  • reacting $$H_2$$ with $$CO_2$$
  • All the above
In the preparation of alkene from alcohol using $$Al_{2}O_{3}$$ which is effective factor?
  • Porosity of $$Al_{2}O_{3}$$
  • Temperature
  • Concentration
  • Surface area of $$Al_{2}O_{3}$$
Choose the correct statement.
671823_dbd604d249c848a3a3f3c336f4f4fcac.png
  • $$A$$ is more volatile than $$B$$
  • $$B$$ is more volatile than $$A$$
  • $$A$$ is formed more rapidly at a higher temperature
  • $$A$$ is formed in higher yield at a low temperature

In the given reaction, number of possible structure is:
659473_ca798db9296c47e7bcf6adfae97e0d5f.png
  • $$1$$
  • $$2$$
  • $$5$$
  • $$6$$
The major product of the reaction is:
631437_693b5a4e6f6e446ea738a7195f4d9fe9.jpg
  • I
  • II
  • III
  • IV
The major product of the following reaction is:
629601_1ed08841a11b4deda363beeb68067bc2.png
Complete the equation:-
1152363_785920168813400090836f9a990e7c76.PNG
0:0:1


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