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    ALCOHOLS, PHENOLS & ETHERS Ques

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    ALCOHOLS, PHENOLS & ETHERS Ques

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    ALCOHOLS, PHENOLS & ETHERS Ques

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    aryaveer376

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    © All Rights Reserved
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    of 12

    QUESTION BANK CHAPTER 7-

    ALCOHOLS, PHENOLS AND ETHERS

    SECTION-A (MULTIPLE CHOICE QUESTIONS)


    1. Phenol on reduction with H2 in the Presence of Ni Catalyst gives
    . benzene
    a. toluene
    b. cyclohexane
    c. Cyclohexanol

    2. Chloro-Ethane reacts with which of the Following to Give Diethyl Ether?


    . NaOH
    a. H2SO4
    b. C2H5ONa
    c. Na2S2O3

    3. Catalytic Dehydrogenation of Primary Alcohol gives a


    . Ketone
    a. Aldehyde
    b. Alcohol
    c. Ester

    4. Due to An ether is More Volatile than an Alcohol having the


    same Molecular Formula.
    . The dipolar character of ether
    a. Alcohols having resonance structures
    b. Intermolecular hydrogen bonding in ethers
    c. Intermolecular hydrogen bonding in alcohols

    5. An Organic Compound with a Pleasant Odor and 78 Degrees Boiling Point is


    boiled with Concentrated H2SO4. It gives a Colorless gas that Decolorizes
    Bromine Water and Alkaline Potassium Permanganate. What is this Organic
    Compound?
    . C2H5COOCH3
    a. C2H5OH
    b. C2H5Cl
    c. C2H6
    6. The Compound Obtained by the Reaction of Propene with Diborane
    Followed by Hydrolysis with Alkaline H2O2 is
    . Tripropylborane
    a. propan-2-ol
    b. Propan-1-ol
    c. Propane

    7. Which of the Following is Formed when Phenol is Exposed to Air?


    1
    . o-Benzoquinone
    a. p-Benzoquinone
    b. Phenoquinone
    c. o-and p-Benzoquinone

    8. Which of the Following is Formed when Glycerol is heated with Oxalic Acid
    at 503K?
    . Glyceric acid
    a. Acrolein
    b. Allyl alcohol
    c. Methanoic acid

    9. Which of the following is true?


    . Lower alcohols are liquid at room temperature and the higher ones are solid
    a. Lower alcohols and higher alcohols, both are liquid at room temperature
    b. Higher alcohols are liquid at room temperature and the lower ones are solid
    c. Both lower and higher alcohols are solid at room temperature

    10. A compound X with the molecular formula C2H8O can be oxidised to


    another compound Y whose molecular formulae is C3H6O2. The compound
    X may be
    (a) CH3CH2OCH3
    (b) CH3CH2CHO
    (c) CH3CH2CH2OH
    (d) CH3CHOHCH3

    ASSERTION REASON QUESTIONS


    Note : In the following questions a statement of assertion followed by a statement
    of reason is given. Choose the correct answer out of the following choices.
    a) Assertion and reason both are correct and reason is correct explanation of assertion.
    b) Both assertion and reason are correct statements but reason is not correct explanation

    2
    of assertion
    c) Assertion is correct statement but reason is wrong statement.
    d) Assertion is wrong statement but reason is correct statement.
    e) Assertion and reason both are wrong statements.

    1. Assertion : Addition reaction of water to but-1-ene in acidic medium yields


    butan-1-ol
    Reason: Addition of water in acidic medium proceeds through the formation of
    primary carbocation.
    2. Assertion: Bond angle in ethers is slightly greater than the tetrahedral angle.
    Reason: There is a repulsion between the two bulky (—R) groups.
    3. Assertion: In Lucas test, 3º alcohols react immediately.
    Reason: An equimolar mixture of anhyd. ZnCl2 and conc. HCl is called Lucas
    reagent.
    4. Assertion: With HI, anisole gives phenol and methyl iodide.
    Reason: Iodide ion combines with smaller group to avoid steric hindrance.
    5. Assertion: With HI at 373 K, tert-butyl methyl ether gives tert-butyl iodide and
    methanol.
    Reason: The reaction occurs by SN2 mechanism.

    SECTION-B (VERY SHORT ASWER TYPE QUESTION) 2 M


    1. Answer the following:
    i. What is the order of dehydration of primary, secondary and tertiary
    alcohols?

    ii. Arrange Pentan-1-ol, n-butane, pentanal, ethoxy ethane in increasing


    order of boiling point?
    2. Give reason for the following
    i. Phenol has smaller dipole moment than methanol.
    ii. Phenol is more acidic than alcohol in nature.
    3. How will you distinguish between primary, secondary and tertiary alcohols?

    3
    4. While separating a mixture of ortho and para-nitro phenols by steam
    distillation, name the isomer which will be steam volatile. Give reasons.

    5. How -OH group attached to carbon in the benzene ring activates benzene
    towards electrophilic substitution?
    6. An organic compound ‘A’ having molecular formula C6H6O gives a
    characteristic colour with aqueous FeCl3 solution. When ‘A’ is treated with
    CO2 and NaOH at 400K under pressure ‘B’ is obtained. The compound ‘B’
    on acidification gives compound ‘C’ which react with acetyl chloride to form
    ‘D’ which is a popular pain killer. Deduce the structure of A, B, C and D.

    4
    7. Complete the following reactions: (any two for 2 marks)
    a) CH3CH2OH + H2SO4 (443K) 
    b) CH3-CH2-CH2-O-CH3 + HBr 
    c) CH3CH2OH + Na 
    d) CH3CH2OH + H2SO4 (413K) 

    8. Give names of the reagents to bring about the following transformations:


    (i) Ethanoic acid to ethanol
    (ii) Propane-1-ol to propanal

    9. How will you distinguish between the following pairs of compounds?


    (i) Pentan-2-ol and pentan-3-ol ii) Phenol and ethanol

    10. Name the reagent of the following reaction. (any 2 for 2 marks)
    i) Oxidation of primary alcohol to carboxylic acid
    ii) Bromination of phenol to 2,4,6-tribromophenol.
    iii) Benzyl alcohol to benzoic acid
    iv) Butan-2-one to butan-2-ol
    How would you obtain
    i) Picric acid from phenol
    ii) 2 Methyl Propene from 2 methyl propanol ?
    11. How will you convert
    i) Propene to propan-1-ol ii) Ethanol to propan-2-ol

    ii)

    12. How would you convert the following :


    i) Phenol to benzoquinone
    ii) Propomone to 2-Methyl propam-2-ol
    Ans:

    13. Account for the following


    i) Preparation of ethers by acid dehydration of secondary or tertiary
    alcohols is not a suitable method.
    ii) Ortho-nitro phenol is more acidic than ortho-methyl phenol

    SECTION-C(short answer type ques) 3M

    14. Write the reaction involved in i) Kolbes reaction ii)Williamson synthesis


    ii) Reimer-Tiemann reaction
    5
    ii) Williamson synthesis

    iii) Reimer-Tiemann reaction

    6
    15. Write the mechanism of hydration of ethene to yield ethanol.

    16. Complete the following reactions.

    7
    17.

    18. Match the items of column I with column II


    Column I Column II
    (i) Methanol (a) Conversion of phenol to
    o- hydroxysalicylic acid
    (ii) Kolbe’s reaction (b) Ethyl alcohol
    (iii) Williamson’s synthesis (c) Conversion of phenol to
    salicylaldehyde
    (iv) Conversion of 2° alcohol to ketone (d) Wood spirit
    (v) Reimer-Tiemann reaction (e) Heated copper at 573K
    (vi) Fermentation (f) Reaction of alkyl halide with
    sodium alkoxide

    20.(a) Name the starting material used in the industrial preparation of phenol.
    (b) Write complete reaction for the bromination of phenol in aqueous and
    non aqueous medium.
    (c) Explain why Lewis acid is not required in bromination of phenol?

    21. (A), (B) and (C) are three non-cyclic functional isomers of a carbonyl
    compound with molecular formula C4H80. Isomers (A) and (C) give positive
    Tollens’ test whereas isomer (B) does not give Tollens’ test but gives positive
    Iodoform test. Isomers (A) and (B) on reduction with Zn (Hg)/conc. HCl,
    give the same product (D). Write the structures of (A), (B), (C) and (D).

    SECTION-D (Case study Based Questions) 4M

    1. Read the passage given below and answer the following questions:
    A compound (X) containing C, Hand O is unreactive towards sodium. It also does not
    react with Schiff's reagent. On refluxing with an excess of hydroiodic acid, (X) yields
    only one organic product (Y). On hydrolysis, (Y) yields a new compound (Z) which can
    be converted into (Y) by reaction with red phosphorus and iodine. The compound (Z)
    on oxidation with potassium permanganate gives a carboxylic acid. The equivalent
    8
    weight of this acid is 60.
    The following questions are multiple choice questions. Choose the most appropriate
    answer:

    (i) The compound (X) is an


    (a) acid (b) aldehyde (c) alcohol (d) ether

    (ii) The IUPAC name of the acid formed is


    (a) methanoic (b) ethanoic (c) propanoic (d) butanoic
    acid acid acid acid.

    9
    (iii) Compound (Y) is
    (a) ethyl (b) methyl (c) propyl (d) mixture of (a)
    iodide iodide iodide and (b).

    (iv) Compound (X) on treatment with excess of Cl2 in presence of light gives
    (a) α - chlorodiethyl (b) α, α' -dichlorodiethyl
    ether ether
    (c) perchlorodiethyl
    (d) none of these.
    ether

    10
    2. Read the given passage and answer the questions that follow:
    Alcohols and phenols are the most important compounds used in
    our daily life. Alcohols are prepared by hydration of alkenes,
    fermentation of glucose, reduction ofaldehydes, ketones, carboxylic
    acids, and esters.
    Alcohols are soluble in water. Boiling points increase with an increase
    in molar mass and decrease with branching. Alcohols on dehydration
    give alkene at 443K, follow thecarbocation mechanism. Excess of
    alcohol at 413K on dehydration with conc.
    H2SO4 also follows a carbocation mechanism but gives diethyl ether.
    Alcohols undergonucleophilic substitution reactions, esterification
    with carboxylic acids and derivativeslike amides, acid halides, acid
    anhydride Phenol is prepared from cumene, diazonium salts, anisole,
    chlorobenzene. Phenol is used to prepare salicylaldehyde, salicylic
    acid, aspirin, methyl salicylate, p-benzoquinone. Phenol undergoes
    electrophilic substitutionreaction at o & p-position. Ethers are
    functional isomers of alcohols, have low boiling points. Ethers are
    used as solvents. Unsymmetrical ethers are prepared by Williamson
    synthesis. Ethers react with HI and undergo SN1 or SN2 mechanisms
    depending upon the stability of carbocation formed. Aromatic ethers
    like anisole undergo electrophilic substitution at o & p – position.
    Answer the following questions:

    Q1.The IUPAC name of

    (a)2-
    methy
    lbutan
    ol
    (b)2-
    methy
    lbutan
    -2-ol
    (c)Me
    thylbu
    tan-2-
    ol
    (d)2-
    methy
    lpropa
    n-2-ol

    Q 2. Out of tert, butyl alcohol, and n-butanol, which will


    undergo dehydrationfaster?
    (a) tert, butyl alcohol
    (b) n-butanol
    (c) Both have the same tendency
    (d) None undergo dehydration

    Q 3. Complete the reaction

    Q 4. Why is C—OH bond length in CH3OH longer than C—OH bond


    length inphenol?

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