MULTIPLE CHOICE QUESTIONS of phenol of Pharmaceutical Organic Chemistry, 3rd semester B.Pharmacy.
1. Phenol is
- a) Solid
- b) Crystalline solid
- c) Gas
- d) Liquid
Answer- b) Crystalline solid
2. Phenol is stronger acid than water and itself it is
- a) Weakly basic
- b) Weakly acidic
- c) Alkali
- d) Strong acid
Answer- b) Weakly acidic
3. Phenol undergoes ionisation to become more stable by reacting with
- a) Positive ions
- b) Negative ions
- c) Both a and b
- d) Neutral atoms
Answer- b) Negative ions
4. Melting point of phenol is relatively high for an aryl compound because of the
- a) Covalent bonding
- b) Ionic bonding
- c) Hydrogen bonding
- d) All of them
Answer- c) Hydrogen bonding
5. Phenol reacts readily then benzene, so it is a
- a) Electrophile
- b) Nucleophile
- c) Protophile
- d) Both a and b
Answer- a) Electrophile
6. Which of the following is used in the manufacture of bakelite?
- a) Phenol
- b) Formaldehyde
- c) Ethyl alcohol
- d) Both a and b
Answer- d) Both a and b
7. Which of the following is most acidic?
- a) Benzyl alcohol
- b) Cyclohexanol
- c) Phenol
- d) m-chlorophenol
Answer- d) m-chlorophenol
8. Phenol is less acidic than
- a) Ethanol
- b) O-nitrophenol
- c) O-methyl phenol
- d) O-methoxy phenol
Answer- b) O-nitrophenol
9. Phenol is more readily soluble in
- a) NaOH solution
- b) Dil. HCI
- c) Both a and b
- d) NaHCO3
Answer- a) NaOH solution
10. Picric acid forms when phenol reacts with
- a) Hydrogen
- b) Nitric acid
- c) Sulphuric acid
- d) Formaldehyde
Answer- b) Nitric acid
11. 2,4,6- Tribromo phenol forms when phenol reacts with
- a) Formaldehyde
- b) Nitric acid
- c) Hydrogen
- d) Bromine
Answer- d) Bromine
12. Phenols are derivative of
- a) Benzene
- b) Alkanes
- c) Alkenese Jogir
- d) Alkynes
Answer- a) Benzene
13.Phenol can be distinguished from ethanol by the reaction with
- a) Br₂/water
- b) Na
- c) Neutral FeCl3
- d) All of above
Answer- a) and C)
14. Phenol is better Bronsted acid than cyclohexanol because
- a) It is a better proton donor
- b) The cyclohexyl group in an electron donating group by induction, which stabilizes the anion formed in the reaction
- c) Phenol is able to stabilize the anion formed in the reaction by resonance
- d) None of above
Answer- c) Phenol is able to stabilize the anion formed in the reaction by resonance
15. Phenol can be prepared by the reaction between
- a) Aniline and HNO, at 373K
- b) CH.MgBr and CO, followed by hydrolysis
- c) CH.SO,Na and NaOH at 623K followed by acidification
- d) CH₂Cl and NaOH at 373K
Answer- c) CH.SO,Na and NaOH at 623K followed by acidification
16. Choose the correct order related to acidic strength
- a) Phenol > water > ethyl alcohol
- b) Ethyl alcohol > water > phenol
- c) Ethyl alcohol > phenol > water
- d) Water > phenol > ethyl alcohol
Answer- a) Phenol > water > ethyl alcohol
17. The distillation of phenol with zinc dust gives
- a) C6H12
- b) C6H6
- c) C6H5 -C6H5
- d) C6H5-OC6H5
Answer- b) C6H6
18. Treatment of phenol with nitrous acid (NaNO2 + HCI) gives mainly
- a) p-nitrophenol
- b) picric acid
- c) m-nitrophenol
- d) p-nitrosophenol
Answer- d) p-nitrosophenol
19. Which of the following statements are correct for phenol?
- a) Phenol is more acidic than phenol
- b) Phenol is used in the production of melamine plastic
- c) Phenol gives violet colour with neutral ferric chloride solution
- d) Phenol when heated with acetyl chloride give phemetole
- (i) a and b
- (ii) a and c
- (iii) c and d
- (iv) a and d
Answer-(ii) a and c
20. Boiling point of phenols are higher than those of corresponding hydrocarbon and aryl halide because-
- a) Strong association of molecules by intermolecular hydrogen bonding
- b) Strong association of molecules by intramolecular hydrogen bonding
- c) Both (a) and (b)
- d) None of above
Answer- a) Strong association of molecules by intermolecular hydrogen bonding
21. Choose correct order of acidity for following
- a) o-cresol > p-cresol > m-cresol
- b) p-cresol> o-cresol > m-cresol
- c) m-cresol > p-cresol > o-crèsol
- d) m-cresol > o-cresol > p-cresol
Answer- c) m-cresol > p-cresol > o-crèsol
22. Phenol recuts with bromine in chloroform at low temperature to give
- a) m-bromophenol
- b) mixture of ortho and para-bromophenol
- c) p-bromo phenol
- d) 2,4,6-Tribromophenol
Answer- b) mixture of ortho and para-bromophenol
23. Electron withdrawing substituents
- a) Stabilise the phenoxide ion and increase the acidity of phenol
- b) Stabilise the phenoxide ion and decrease the acidity of phenol
- c) Stabilise the phenoxide ion and neutralise the acidity of phenol
- d) None of above
Answer- a) Stabilise the phenoxide ion and increase the acidity of phenol
24. Sulphonation of phenol at room temperature gives
- a) p-isomer
- b) o-isomer
- c) Both a and b
- d) None of above
Answer- b) o-isomer
25. Sulphonation of phenol at 370K gives
- a) p-isomer
- b) o-isomer
- c) m-isomer
- d) Both a and b
Answer- a) p-isomer
26. Which statement is correct relative to Electron releasing group on phenol
- a) Stabilise the phenoxide ion and increase the acidity
- b) Destabilise the phenoxide ion and decrease the acidity
- c) Destabilise the phenoxide ion and increase the acidity
- d) Stabilise the phenoxide ion and decrease the acidity
Answer- b) Destabilise the phenoxide ion and decrease the acidity
