JEE Chemistry Alcohols Phenols and Ethers MCQs Set C

Question: Which of the following are correct statement(s) ?

(i) Polar nature of O–H bond is responsible for acidic character of alcohols.

(ii) Acidic strength of alcohols follow the order 1° > 2° > 3°.

(iii) Alcohols are stronger acids than water.

(iv) Alcohols also react as Bronsted base.

• a) (i), (ii) and (iv)
• b) (i), (iii) and (iv)
• c) (i), (ii) and (iii)
• d) (ii), (iii) and (iv)

Answer: (i), (ii) and (iv)

Question: Read the following statements and choose the correct option.

(i) Ethanol on dehydration at 443 K gives ethene

(ii) Ethanol on dehydration at 413 K gives diethyl ether

(iii) Only primary alcohols on dehydration give ethers.

(iv) Secondary and tertiary alcohols on dehydration give ethers having 2° and 3° carbon attached with O atom.

• a) TTTF
• b) TTFF
• c) TFTF
• d) FTTF

Answer: TTTF

Question: Which of the following statements are correct ?

(i) In phenols, the —OH group is attached to sp² hybridised carbon of an aromatic ring

(ii) The carbon – oxygen bond length (136 pm) in phenol is slightly more than that in methanol

(iii) Partial double bond character is due to the conjugation of unshared electron pair of oxygen with the aromatic ring.

(iv) sp² hybridised state of carbon to which oxygen is attached.

• a) (i), (iii) and (iv)
• b) (i), (ii) and (v)
• c) (i), (ii) and (iii)
• d) (i) and (iv)

Answer: (i), (iii) and (iv)

Question: Which of the following statements are correct ?

(i) Ethanol mixed with methanol is called denatured alcohol.

(ii) Excess of methanol in body may cause blindness.

(iii) In the body methanol is oxidised to methanoic acid.

(iv) A methanol poisoned patient is treated by giving intravenous injections of ethanoic acid.

• a) (i), (ii) and (iii)
• b) (i) and (v)
• c) (ii), (iii) and (iv)
• d) None of these

Answer: (i), (ii) and (iii)

Question:

• a) A – (q), B – (r), C – (s), D – (p)
• b) A – (s), B – (q), C – (p), D – (r)
• c) A – (r), B – (p), C – (s), D – (q)
• d) A – (q), B – (p), C – (s), D – (r)

Answer: A – (q), B – (r), C – (s), D – (p)

Question:

• a) A – (q), B – (p), C – (s), D – (r)
• b) A – (r), B – (q), C – (p), D – (s)
• c) A – (q), B – (s), C – (p), D – (r)
• d) A – (s), B – (r), C – (q), D – (p)

Answer: A – (q), B – (p), C – (s), D – (r)

Question:

• a) A – (r), B – (s), C – (q), D – (p)
• b) A – (s), B – (q), C – (p), D – (r)
• c) A – (s), B – (q), C – (r), D – (p)
• d) A – (p), B – (r), C – (q), D – (s)

Answer: A – (r), B – (s), C – (q), D – (p)

Question:

Assertion : The bond angle in alcohols is slightly less than the tetrahedral angle.
Reason : In alcohols, the oxygen of –OH group is attached to sp³ hybridized carbon atom.

• a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
• b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion.
• c) Assertion is correct, reason is incorrect
• d) Assertion is incorrect, reason is correct

Answer: Assertion is correct, reason is correct; reason is a correct explanation for assertion

Question:

Assertion : In Lucas test, 3º alcohols react immediately.
Reason : An equimolar mixture of anhyd. ZnCl₂ and conc. HCl is called Lucas reagent.

• a) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• b) Assertion is correct, reason is incorrect
• c) Assertion is incorrect, reason is correct
• d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: Assertion is correct, reason is correct; reason is not a correct explanation for assertion

Question: 

Assertion : Reimer-Tiemann reaction of phenol with CCl₄ in NaOH at 340 K gives salicyclic acid as the major product.
Reason : The reaction occurs through intermediate formation of dichlorocarbene.

• a) Assertion is correct, reason is incorrect.
• b) Assertion is incorrect, reason is correct
• c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• d) None of these

Answer: Assertion is correct, reason is incorrect.

Question:

Assertion : Phenol is more reactive than benzene towards electrophilic substitution reaction.
Reason : In the case of phenol, the intermediate carbocation is more resonance stabilized.

• a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
• b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• c) Assertion is correct, reason is incorrect
• d) Assertion is incorrect, reason is correct.

Answer: Assertion is correct, reason is correct; reason is a correct explanation for assertion

Question: 

Assertion : In case of phenol, bromination takes place even in absence of Lewis acid whereas bromination of benzene takes place in presence of Lewis acid like FeBr₃.
Reason : – OH group attached to benzene ring is highly deactivating.

• a)  Assertion is correct, reason is incorrect
• b) Assertion is incorrect, reason is correct
• c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: Assertion is correct, reason is incorrect

Question:

• a) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• b) Assertion is correct, reason is incorrect
• c) Assertion is incorrect, reason is correct
• d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: Assertion is correct, reason is correct; reason is not a correct explanation for assertion

Question:

Assertion : Ethers behave as bases in the presence of mineral acids.
Reason : Due to the presence of lone pairs of electrons on oxygen.

• a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
• b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• c) Assertion is correct, reason is incorrect
• d) Assertion is incorrect, reason is correct

Answer: Assertion is correct, reason is correct; reason is a correct explanation for assertion

Question:

Assertion : With HI, anisole gives iodobenzene and methyl alcohol.
Reason : Iodide ion combines with smaller group to avoid steric hindrance.

• a) Assertion is incorrect, reason is correct
• b) Assertion is correct, reason is incorrect
• c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: Assertion is incorrect, reason is correct

Question:

• a) Assertion is correct, reason is incorrect
• b) Assertion is incorrect, reason is correct
• c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: Assertion is correct, reason is incorrect

Question:

Assertion : Ethyl phenyl ether on reaction with HBr form phenol and ethyl bromide.
Reason : Cleavage of C–O bond takes place on ethyloxygen bond due to the more stable phenyl-oxygen bond.

• a) Assertion is correct, reason is incorrect
• b) Assertion is incorrect, reason is correct
• c) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
• d) Assertion is correct, reason is correct; reason is a correct explanation for assertion

Answer: Assertion is correct, reason is incorrect

Question:  Vinyl carbinol is

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question:

• a) 1-Pentanol
• b) Pentane
• c) 2-Pentanol
• d) 1,2-Pentanediol

Answer: 1-Pentanol

Question:

• a) NaBH₄
• b) H₂ / Ni
• c)

  

• d) None of these

Answer:  NaBH₄

Question:  Which of the following reactions will yield phenol?

• a) (i), (ii) and (iii)
• b) (i), (iii) and (iv)
• c) (i) and (iii)
• d) (ii), (iii) and (iv)

Answer: (i), (ii) and (iii)

Question: Hydration of styrene is carried out in presence of acid as catalyst. The major product is

• a) 1–hydroxy–1–phenylethane.
• b) 2–hydroxy–1–phenylethane.
• c) 2–hydroxy–2–phenylethane
• d) 1–hydroxy–2–phenylethane

Answer: 1–hydroxy–1–phenylethane.

Question:  Which of the following reagents can be used for preparation of cumene ?

• a) (ii) and (iii)
• b) (ii) and (iv)
• c) (i) and (ii)
• d) (i), (ii) and (iii)

Answer: (ii) and (iii)

Question: The hydroboration of an alkene is carried out, then on oxidation with hydrogen peroxide, the alcohol so obtained is achiral. Possible structure of alkene is (are) :

(i) 2, 3– dimethylbut–2–ene.
(ii) 3, 4–dimethylbut –3–ene.
(iii) 2–methyl–but–2–ene.
(iv) 2–methylpropene.

• a) (i) and (iv)
• b) (iii) and (iv)
• c) (ii) and (iii)
• d) (i) and (iii)

Answer: (i) and (iv)

Question:

• a) (i), (iii) and (iv)
• b) (ii), (iii) and (iv)
• c) (i), (ii) and (iv)
• d) (i), (ii), (iii) and (iv)

Answer: (i), (iii) and (iv)

Question:  Mechanism of acid catalysed hydration reaction involves

(i) Protonation of alkene to form carbocation by electrophilic attack of H₃O⁺
(ii) Nucleophilic attack of water on carbocation.
(iii) Deprotonation to form alcohol.

• a) (i), (ii) and (iii)
• b) (i) and (ii)
• c)  (i) and (iii)
• d) (ii) and (iii)

Answer: (i), (ii) and (iii)

Question: Phenol is less acidic than

• a) acetic acid
• b) acetylene
• c) p-methoxyphenol
• d) ethanol

Answer: acetic acid

Question:

• a) D > C > A > B
• b) A > B > D > C
• c) B > D > A > C
• d) C > B > A > D

Answer: D > C > A > B

Question:

• a) III > I > II > IV
• b) II > IV > I > III
• c) I > II > III > IV
• d) IV > III > I > II

Answer: III > I > II > IV

Question: ClCH₂CH₂OH is stronger acid than CH₃CH₂OH because of:

• a) – I effect of Cl disperses negative charge on O atom to produce more stable anion
• b) None of these
• c) – I effect of Cl disperses negative charge on O atom to produce more stable cation
• d) – I effect of Cl increases negative charge on O atom of alcohol

Answer: – I effect of Cl disperses negative charge on O atom to produce more stable anion

Question: Which one of the following compounds will be most readily attacked by an electrophile ?

• a) Phenol
• b) Chlorobenzene
• c) Benzene
• d) Toluene

Answer: Phenol

Question:

• a) benzoic acid
• b) benzaldehyde
• c) benzene
• d) toluene

Answer: benzoic acid

Question:  When phenol is reacted with CHCl₃ and NaOH followed by acidification, salicylaldehyde is obtained. Which of the following species are involved in the above mentioned reaction as intermediate?

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question:  The reagent used for dehydration of an alcohol is

• a) aluminium oxide
• b) sodium chloride
• c) calcium chloride
• d) phosphorus pentachloride

Answer: aluminium oxide

Question: The alcohol which does not give a stable compound on dehydration is

• a) methyl alcohol
• b) n-Butyl alcohol
• c) ethyl alcohol
• d) n-Propyl alcohol

Answer: methyl alcohol

Question:  A compound of the formula C₄H₁₀O reacts with sodium and undergoes oxidation to give a carbonyl compound which does not reduce Tollen’s reagent, the original compound is

• a)

  

• b) n-Butyl alcohol
• c) Diethyl ether
• d) Isobutyl alcohol

Answer:

Question:  Which of the following fact(s) explain as to why p-nitrophenol is more acidic than phenol?

I. –I Effect of nitro group.
II. Greater resonance effect of p-nitrophenoxy group
III. Steric effect of bulky nitro group.

• a) I and II
• b) II and III
• c) I and III
• d) II alone

Answer:  I and II

Question:

• a)

  

• b) butanal
• c) propanal
• d) n-butyl alcohol

Answer:

Question:  Which of the following species can act as the strongest base?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:  Which of the following reagents can be used to oxidise primary alcohols to aldehydes?

(i) CrO₃ in anhydrous medium.
(ii) KMnO₄ in acidic medium.
(iii) Pyridinium chlorochromate.
(iv) Heat in the presence of Cu at 573K.

• a) (i), (iii) and (iv)
• b) (i) and (iii)
• c) (ii), (iii) and (iv)
• d) (i), (iii) and (iv)

Answer: (i), (iii) and (iv)

Question:  Which one of the following will show the highest pH value ?

• a)

  

• b) p–nitrophenol.
• c) o–nitrophenol
• d) None of these

Answer: 

Question: Which of the following is most reactive towards aqueous HBr ?

• a) 1-Phenyl-1-propanol
• b) 1-Phenyl-2-propanol
• c) 3-Phenyl-1-propanol
• d) All are equally reactive

Answer: 1-Phenyl-1-propanol

Question: The major product of the reaction between tert-butyl chloride and sodium ethoxide is

• a) 2-methylprop-1-ene
• b) 2-butene
• c) 1-butene
• d) ethene

Answer:  2-methylprop-1-ene

Question: In Williamson synthesis if tertiary alkyl halide is used than

• a) alkene is the only reaction product
• b) a mixture of alkene as a major product and ether as a minor product forms
• c) ether is obtained in poor yield
• d) ether is obtained in good yield

Answer: alkene is the only reaction product