CBSE Class 12 Chemistry Alcohols Phenols and Ethers MCQs Set 03

Question. An aromatic ether is not cleaved by HI even at 525 K. The compound is
(a) C₆H₅OCH₃
(b) C₆H₅OC₆H₅
(c) C₆H₅OC₃H₇
(d) Tetrahydrofuran

Answer : D

Question. Ethanol when reacted with PCl₅ gives A, POCl₃ and HCl. A reacts with silver nitrite to form B (major product) and AgCl. A and B respectively are         
(a) C₂H₅ C l and C₂H₅OC₂H₅ 
(b) C₂H₆ and C₂H₅OC₂H₅
(c) C₂H₅ C l and C₂H₅NO₂
(d) C₂H₆ and C₂H₅NO₂

Answer : B

Question. Polyvinylalcohol can be prepared by
(a) polymerization of vinyl alcohol
(b) alkaline hydrolysis of polyvinyl acetate
(c) polymerization of acetylene
(d) reaction of acetylene with H2SO4 in presence of HgSO4

Answer : A

Question. Which of the following fact(s) explain(s) 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) I and III
(c) II and III
(d) II alone

Answer : D

Question. ClCH₂CH₂OH is stronger acid than CH₃CH₂OH because of:
(a) – I effect of Cl increases negative charge on O atom of alcohol
(b) – I effect of Cl disperses negative charge on O atom to produce more stable cation
(c) – I effect of Cl disperses negative charge on O atom to produce more stable anion
(d) None of these

Answer : D

Question. The ether that undergoes electrophilic substitution reactions is
(a) CH₃OC₂H₅
(b) C₆H₅OCH₃
(c) CH₃OCH₃
(d) C₂H₅OC₂H₅

Answer : A

Question. A triglyceride can have how many different acyl groups?
(a) 3
(b) 2
(c) 1
(d) 4

Answer : C

Question. In the Victor-Meyer’s test, the colour given by 1°, 2° and 3° alcohols are respectively.
(a) red, colourless, blue
(b) red, blue, colourless
(c) blue, red, violet
(d) red, blue, violet.

Answer : A

Question. Which one of the following is not formed when glycerol reacts with HI ?
(a) CH₃ — CHI — CH₃
(b) CH₃ — CH = CH₂
(c) CH₂OH — CHI — CH₂OH
(d) CH₂ = CH — CH₂I

Answer : C

Question. The reaction of Lucas reagent is fastest with:
(a) (CH₃)₂CHOH
(b) CH₃(CH₂ )₂OH
(c) CH₃CH₂OH
(d) (CH₃)₃COH

Answer : D

Question. Ethanol when reacted with PCl₅ gives A, POCl₃ and HCl. A reacts with silver nitrite to form B (major product) and AgCl. A and B respectively are        
(a) C₂H₅ Cl and C₂H₅OC₂H₅
(b) C₂H₆ and C₂H₅OC₂H₅
(c) C₂H₅Cl and C₂H₅NO₂
(d) C₂H₆ and C₂H₅NO₂

Answer : C

Question. Phenol on reaction with Br2 in non-polar aprotic solvent furnishes
(a) 2, 4, 6-tribromophenol
(b) p-bromophenol
(c) o- and p-bromophenol
(d) m-bromophenol

Answer : C

Question. Among the following the one which reacts most readily with ethanol is
(a) p-nitrobenzyl bromide
(b) p-chlorobenzyl bromide
(c) p-methoxybenzyl bromide
(d) p-methylbenzyl bromide

Answer : D

Question. The most suitable reagent for the conversion of RCH₂OH → RCHO is :           
(a) KMnO₄
(b) K₂Cr₂O₇
(c) CrO₃
(d) PCC (pyridine chlorochromate)

Answer : C

Question. When o- or p -phenol sulphonic acid is treated with bromine water, the product formed is
(a) 2, 4-dibromophenol
(b) 2, 4, 6-tribromophenol
(c) 3-bromophenol boric acid
(d) 3, 5-dibromophenol

Answer : B

Question. The following reaction is known as

(a) Perkin reaction
(b) Gattermann reaction
(c) Kolbe reaction
(d) Gattermann-a.ldehyde reaction

Answer : D

Question. The final product of the following reaction is/are

Answer : B

Question. Phenol on heating with CCI4 and aqueous KOH gives salicylic acid. This reaction is
(a) Friedel-Craft reaction
(b) Diels-Alder reaction
(c) Reimer-Tiemann reaction
(d) Wittig reaction

Answer : C

Question. Among the following, which is least acidic?
(a) phenol
(b) o-cresol
(c) p -nitrophenol
(d) p -chlorophenol

Answer : B

Question. An organic compound ‘X’ with molecular fommla, C₇H₈O is insoluble in aqueous NaHCO₃ but dissolves in NaOH. When treated with bromine water’ X’rapidly gives ‘Y’ C₇H₅OBr₃ . 
The compounds’ X’ and’ Y’ respectively, are
(a) benzyl alcohol and 2, 4, 6-tribromo-3-methoxy benzene
(b) benzyl alcohol and 2, 4, 6-tribromo-3-methyl phenol
(c) o-cresol and 3, 4, 5-tribromo-2-methyl phenol
(d) m-cresol and 2, 4, 6-tribromo-3-methyl phenol

Answer : D

Question. Benzoylation of phenol in alkaline medium is known as
(a) Friedel-Crafts reaction
(b) Wurtz-Fittig reaction
(c) Schotten-Baurnann reaction
(d) Sabatier Senderens reduction

Answer : C

Question. By heating phenol with chloroform in alkali, it is converted into
(a) salicylic acid
(b) salicylaidehyde
(c) anisole
(d) phenyl benzoate

Answer : B