JEE Chemistry Alcohols Phenols and Ethers MCQs Set B

• a) Zymase
• b) Diastase
• c) Invertase
• d) Maltase

Answer: Zymase

Question: An industrial method of preparation of methanol is

• a) catalytic reduction of carbon monoxide in presence of ZnO–Cr₂O₃
• b) by reacting methane with steam at 900ºC with a nickel catalyst
• c) by reducing formaldehyde with lithium aluminium hydride
• d) by reacting formaldehyde with aqueous sodium hydroxide solution

Answer: catalytic reduction of carbon monoxide in presence of ZnO–Cr₂O₃

Question: Ethyl alcohol is industrially prepared from ethylene by

• a) Absorbing in H₂SO₄ followed by hydrolysis
• b) All the three
• c) Catalytic reduction
• d) Permanganate oxidation

Answer:  Absorbing in H₂SO₄ followed by hydrolysis

Question: Drinking alcohol’ is very harmful and it ruins the health. ‘Drinking alcohol’ stands for

• a) drinking ethyl alcohol
• b) drinking methyl alcohol
• c) drinking propyl alcohol
• d) drinking isopropyl alcohol

Answer: drinking ethyl alcohol

Question: The fermentation reactions are carried out in temperature range of

• a) 20-30°C
• b) 40-50°C
• c) 30-40°C
• d) 50-60°C

Answer: 20-30°C

Question: Ethanol is prepared industrially by

• a) Both the above
• b) hydration of ethylene
• c) fermentation of sugar
• d) None of these

Answer: Both the above

Question: The fermentation of starch to give alcohol occurs mainly with the help of

• a) enzymes
• b) air
• c) O₂
• d) CO₂

Answer: enzymes

Question: In the commercial manufacture of ethyl alcohol from starchy substances by fermentation method. Which enzymes slipwise complete the fermentation reaction

• a) Diastase, maltase and zymase
• b) Maltase, zymase and invertase
• c) Diastase, zymase and lactase
• d) Diastase, invertase and zymase

Answer: Diastase, maltase and zymase

Question: Methyl alcohol is toxic. The reason assigned is

• a) it reacts with nitrogen and forms CN^– in the lungs
• b) it stops respiratory track
• c) it increses CO₂ content in the blood
• d) it is a reduction product of formaldehyde

Answer: it reacts with nitrogen and forms CN^– in the lungs

More Questions..................................................

Question: In order to make alcohol undrinkable pyridine and methanol are added to it. The resulting alcohol is called

• a) Denatured spirit
• b) Power alcohol
• c) Proof spirit
• d) Poison alcohol

Answer: Denatured spirit

Question: Wine (alcoholic beverages) contains

• a) C₂H₅OH
• b) CH₃OH
• c) Glycerol
• d) 2-propanol

Answer: C₂H₅OH

Question:  Tonics in general contain

• a) Ethanol
• b) Ether
• c) Methanol
• d) Rectified spirit

Answer: Ethanol

Question: Widespread deaths due to liquor poisoning occurs due to

• a) presence of methyl alcohol in liquor
• b) presence of lead compounds in liquor
• c) presence of ethyl alcohol in liquor
• d) presence of carbonic acid in liquor

Answer:  presence of methyl alcohol in liquor

Question: Select the incorrect statement about the fermentation

• a) Carbon monoxide is released during fermentation
• b) Fermentation takes place in anaerobic conditions
• c) When grapes are crushed, sugar and the enzyme come in contact and fermentation starts
• d) If air gets into fermentation mixture, the oxygen of air oxidises ethanol to ethanoic acid which in turn destroys the taste of alcoholic drinks

Answer: Carbon monoxide is released during fermentation

Question: Denaturation of alcohol is the

• a) mixing of CuSO₄ (to give the colour) and pyridine (a foul smelling solid) to make the commercial alcohol unfit for drinking
• b) mixing of Cu(OAc)₂ and ammonia to make the commercial alcohol unfit for drinking
• c) mixing of Cu(OAc)₂ and pyridine to make the commercial alcohol unfit for drinking
• d) None of these

Answer: mixing of CuSO₄ (to give the colour) and pyridine (a foul smelling solid) to make the commercial alcohol unfit for drinking

Question: Which one is formed when sodium phenoxide is heated with ethyl iodide

• a) Phenetole
• b) Phenol
• c) Ethyl phenyl alcohol
• d) None of these

Answer: Phenetole

Question: Williamson’s synthesis is used to prepare

• a) diethyl ether
• b) bakelite
• c) acetone
• d) P.V.C

Answer: diethyl ether

Question: The reaction of sodium ethoxide with ethyl iodide to form diethyl ether is termed

• a) nucleophilic substitution
• b) electrophilic addition
• c) radical substitution
• d) electrophilic substitution

Answer: nucleophilic substitution

Question: Ethanol and dimethyl ether form a pair of functional isomers. The boiling point of ethanol is higher than that of dimethyl ether, due to the presence of

• a) H-bonding in ethanol
• b) H-bonding in dimethyl ether
• c) CH₃ group in ethanol
• d) CH₃ group in dimethyl ether

Answer: H-bonding in ethanol

Question: Ether which is liquid at room temperature is

• a) C₂H₅OC₂H₅
• b) C₂H₅OCH₃
• c) CH₃OCH₃
• d) None of these

Answer: C₂H₅OC₂H₅

Question: Ether can be used

• a) All of the above
• b) In perfumery
• c) As a refrigerant
• d) As a general anaesthetic

Answer: All of the above

Question: Which of the following compound is soluble in ether?

• a) Oils and fats
• b) Water
• c) NaCl
• d) PCl₅

Answer: Oils and fats

Question: An ether is more volatile than an alcohol having the same molecular formula. This is due to

• a) Inter-molecular hydrogen bonding in alcohols
• b) Inter-molecular hydrogen bonding in ethers
• c) Alcohols having resonance structures
• d) Dipolar character of ethers

Answer: Inter-molecular hydrogen bonding in alcohols

Question: Which of the following has strongest hydrogen bonding?

• a) Ethyl alcohol
• b) Ethyl amine
• c) Ethanal
• d) Diethyl ether

Answer: Ethyl alcohol

Question: Oxygen atom in ether is

• a) comparatively inert
• b) very active
• c) replaceable
• d) active

Answer: comparatively inert

Question: The ether that undergoes electrophilic substitution reactions is

• a) C₆H₅OCH₃
• b) CH₃OC₂H₅
• c) CH₃OCH₃
• d) None of these

Answer: C₆H₅OCH₃

Question:  Diethyl ether on heating with conc. HI gives two moles of

• a) ethyl iodide
• b) ethanol
• c) iodoform
• d) methyl iodide

Answer: ethyl iodide

Question: Methylphenyl ether can be obtained by reacting

• a) phenolate ions and methyl iodide
• b) methoxide ions and bromobenzene
• c) methanol and phenol
• d) bromo benzene and methyl bromide

Answer: phenolate ions and methyl iodide

Question: Diethyl ether can be decomposed by heating with

• a) HI
• b) Water
• c) NaOH
• d) KMnO₄

Answer: HI

Question: An aromatic ether is not cleaved by HI even at 525 K. The compound is

• a) C₆H₅OC₆H₅
• b) C₆H₅OCH₃
• c) Tetrahydrofuran
• d) None of these

Answer: C₆H₅OC₆H₅

Question: When 2-methoxypropane is heated with HI, in the mole ratio 1 : 1, the major products formed are

• a) methyl iodide and 2-propanol
• b) methyl iodide and 2-iodopropane
• c) methanol and 2-propanol
• d) methanol and 2-iodopropane

Answer: methyl iodide and 2-propanol

Question: Formation of diethyl ether from ethanol is based on a

• a) dehydration reaction
• b) dehydrogenation reaction
• c) hydrogenation reaction
• d) heterolytic fission reaction

Answer: dehydration reaction

Question: The cleavage of an aryl-alkyl ether with cold HI gives

• a) phenol and alkyl iodide
• b) alkyl iodide, aryl iodide and water
• c) aryl iodide and water
• d) alkyl iodide and water

Answer: phenol and alkyl iodide

Question: Which of the following compounds is resistant to nucleophilic attack by hydroxyl ions

• a) Diethyl ether
• b) Acetonitrile
• c) Methyl acetate
• d) Acetamide

Answer: Diethyl ether

Question: When an alcohol is prepared by reaction of ethylmagnesiumbromide with 2–pentanone, product formed does not rotate plane polarised light. For this reaction which of the following statement(s) is/are correct ?

(i). Product formed is achiral.
(ii) Racemic mixture is formed.

• a) Statement (ii) is correct only
• b) Both statements (i) and (ii) are incorrect
• c) Both statements (i) and (ii) are correct
• d) None of these

Answer: Statement (ii) is correct only