12th class (Fsc) Chemistry unit 11 MCQs
26. Denatured alcohol is known as:
a. Methylated spirit
b. Absolute alcohol
c. Rectified spirit
d. Wood spirit
27. Which is most acidic?
a. C2H5OH
b. H2O
c. CH3 -CH2 – CH2OH
d. CH3 OH
28. In intermediate in acid catalyst dehydration of alcohol is:
a. Carbocation
b. Carbon
c. Free radical
d. Carbanion
29. If a nucleophile attacks, then it is …… bond which breaks:
a. C-C bond
b. C-O bond
c. H-H bond
d. O-H bond
30. If electrophile attacks. then it is …… bond which breaks.
a. C-C bond
b. C-O bond
c. H-H bond
d. O-H bond
31. When nucleophile attacks on an alcohol, which bond break:
a. O-H bond
b. C-O bond
c. C-C bond
d. C-H bond
32. The most reactive alcohol when C-O bond breaks is:
a. Pro..alcohol
b. Ter.alcohol
c. Sec.alcohol
d. None of these
33. Which of the following has most acidic proton:
a. Phenol
b. Thinol
c. Ether
d. Alcohol
34. Oxidation of methyl alcohol gives:
a. Ester
b. Fromaldehyde
c. Acid
d. Acetone
35. Which of the following compound will not be easily oxidize?
a. Tertiary alcohol
b. Primary alcohol
c. Aldehyde
d. Secondary alcohol
36. Phenol os commonly known as:
a. Carboxylic acid
b. Carbolic acid
c. Amino acid
d. Phenolic acid
37. In phenol-OH group is directly attached to the carbon atom of:
a. Branched chain
b. Closed chain
c. Benzene ring
d. Straight chain
38. Dow;s process is used for the preparation of:
a. Phenols
b. Esters
c. Alcohols
d. Ethers
39. Phenol is used:
a. As antiseptic
b. In alcoholic beverages
c. As mouth repellant
d. As anesthetic
40. Phenol is acidic because of:
a. Localized bonding
b. Resonance effect
c. Inductive effect
d. None of these
41. The pH of solution of phenol is:
a. 1-2
b. 5-6
c. 3-4
d. 6-7
42. The K4 value of phenol is 1.3×10-10 which indicates that it is very:
a. Weak base
b. Strong base
c. Weak acid
d. Strong acid
43. Phenol reacts with a base to form:
a. Ester
b. Benzene
c. Salt
d. Toluene
44. Which inorganic reagent may be used to distinguish between phenol and methanol:
a. K2Cr2O-in dil H2SO4
b. Alkaline aqueous I2
c. Na
d. Aqueous NaHCO3
45. Which of the following is more reactive:
a. Nitro benzene
b. Benzene
c. Benzoic acid
d. Phenol
46. Which of the following scientists was obtained carbolic acid from coal tar in 1834?
a. Runge
b. Hoffman
c. Kekule
d. Dewar
47. In dow’s process vapours of chlorobenzene are passed through?
a. 15% KOH
b. 20% NaOH
c. 10% KOH
d. 10% NaOH
48. Picric acid is a …… which behave like an acid:
a. Alkane
b. Ether
c. Alcohol
d. None of these
49. A plastic bakelite is a compound of HCHO with:
a. Na
b. Benzene
c. CH3COCI
d. NH2NO3
50. The reagent used for testing phenolic group is:
a. Na
b. FeCI3
c. CH3COCI
d. NH4NO3