CBSE Class 11 Chemistry Organic Chemistry Some Basic Principles and Techniques MCQs Set B

Question: The number of meso-forms in the following compound is
HOOC- CH(CH₃ )· CH(OH)· CH(Cl)· CH(OH)CH(CH₃ )· COOH 
a) 3
b) 4
c) 8
d) 16
Answer: b

Question: Which of the following compounds is optically active ?
a) 1-butanol
b) Isopropyl alcohol
c) Acetaldehyde
d) 2-butanol
Answer: d 

Question: Which of these contains the carbonyl group?
a) ketones
b) aldehydes
c) esters
d) all of these
Answer: d

Question: Butanone is a four-carbon compound with the functional group –
a) carboxylic acid
b) aldehyde.
c) ketone
d) alcohol.
Answer: c

Question: The number of primary, secondary and tertiary carbons in 3, 4-dimethylheptane are respectively
a) 4, 3 and 2
b) 2, 3 and 4
c) 4, 2 and 3
d) 3, 4 and 2
Answer: a

Question: The total number of isomers for C₄H₈ is
a) 5
b) 6
c) 7
d) 8
Answer: b

Question: Isomers of propionic acid are
a) HCOOC₂H₅ and CH₃COOCH₃
b) HCOOC₂H₅ and C₃H₇COOH
c) CH₃COOCH₃ and C₃H7OH
d) C₃H₇OH and CH₃COCH₃
Answer: a

Question: In laboratory, first organic compound was synthesised by
a) Kekule
b) Hennel
c) Wohler
d) Liebig
Answer: c

Question: Which of the following scientist proposed that a ‘vital force’ was responsible for the formation of organic compounds ?
a) Berzilius
b) Wohler
c) Berthelot
d) Kolbe
Answer: a

Question: The percentage of s- character of the hybrid orbitals in ethane, ethene and ethyne are respectively.
a) 50, 75, 100
b) 10, 20, 40
c) 25, 33, 50
d) 25, 50, 75
Answer: c

Question: Tautomerism is exhibited by

Answer: a

Question: Which of the following carbocations is least stable?
a) tert-Alkyl
b) sec-Alkyl
c) pri-Alkyl
d) Methyl
Answer: d

Question: 2- Pentene contains
a) 15 σ- and one π- bond
b) 14 σ-and one π- bond
c) 15 σ- and two π- bonds
d) 14 σ- and two π- bonds
Answer: b

Question: CH₃CH₂OH and CH₃OCH₃ are the examples of
a) chain isomerism
b) functional isomerism
c) position isomerism
d) metamerism
Answer: b

Question: Which of the following compounds is isomeric with 2, 2, 4, 4- tetramethylhexane?
a) 3-ethyl -2, 2- dimethylpentane
b) 4-isopropylheptane
c) 4-ethyl-3-methyl-4-n propyloctane
d) 4, 4-diethyl-3-methylheptane
Answer: b

Question: Among the following four structures I to IV

it is true that
a) all fow- are chiral compounds
b) I and II are chiral compounds
c) only ill is a chiral compound
d) IT and IV are chiral compounds
Answer: b

Question: The hybridisation of carbon atom in C — C single bond of H₂C = CH — CH = CH₂ is
a) sp³ — sp
b) sp² — sp
c) sp² — sp²
b) sp³ — sp³
Answer: c

Question: In the hydrocarbon CH₃ – CH = CH – CH₂ – C ≡ CH
6 5 4 3 2 1

 The state of hybrization of carbons 1, 3 and 5 are in the following sequence 
a) sp², sp, sp³
b) sp, sp³, sp²
c) sp, sp², sp³
d) sp³, sp², sp
Answer: b

Question: Which of the following is incorrectly matched –
a) vinegar →carboxylic acid
b) C₂H₆ →alkane
c) ethanol →alcohol
d) methanol →ketone
Answer: d

Question: The absolute configuration of the following

a) 2S, 3R
b) 2S, 3S
c) 2R, 3S
d) 2R, 3R
Answer: b

Question: The discovery that shook the belief in the vital force theory was
a) Stereoisomerism
b) Synthesis of indigo
c) Wholer’s synthesis of urea from ammonium cyanate
d) Fermentation of sugars
Answer: c

Question: The IUPAC name of CH₃COCH (CH₃)₂ is -
a) isopropyl methyl ketone
b) 2-methyl-3-butanone
c) 4-methylisopropyl ketone
d) 3-methyl-2-butanone
Answer: d

Question: Who is known as the “Father of Chemistry”?
a) Faraday
b) Priestley
c) Rutherford
d) Lavoisier
Answer: d

Question: Which are isomers ?
a) ethyl alcohol and dimethyl ether
b) acetone and acetaldehyde
c) propionic acid and propanone
d) methyl alcohol and dimethyl ether
Answer: a

Question: The functional group present in CH₃COOC₂H₅ is –
a) ketonic
b) aldehydic
c) ester
d) carboxylic
Answer: c

Question: Which of the following have incorrect molecular formula?
A. Icosane – C₁₀H₂₂
B. Triacontane – C₃₀H₆₂
C. Nonane – C₉H₂0
D. Heptane – C₇H₁₄
a) (a) and (d)
b) Only (d)
c) (b) and (d)
d) Only (b)
Answer: a

Question: The compound which has one isopropyl group is
a) 2, 2, 3, 3 - Tetramethylpentane
b) 2, 2 - Dimethylpentane
c) 2, 2, 3- Trimethylpentane
d) 2- Methypentane
Answer: d

Question:

Compound can exhibit
a) geometrical isomerism
b) tautomerism
c) optical isomerism
d) geometrical and optical isomerism
Answer: c

Question: The successive members in a homologues series differ from each other by ________
a) – CH₂CH₂ ^– unit
b) – CH₂ unit
c) – OCH3 unit
d) – CH₃ unit
Answer: b

Question: An aromatic compound of formula C₇H₇Cl has in all ..... isomers :
a) 5
d) 2
c) 4
d) 3
Answer: c

Question: Geometrical isomerism is possible in
a) acetone oxime
b) isobutene
c) acetophenone oxime
d) benzophenone oxime
Answer: c

Question: Ethers are isomeric with
a) aldehydes
b) ketones
c) both aldehydes and ketones
d) alcohols
Answer: d

Question: Which of the following organic compound was synthesised by F. Wohler from an inorganic compound?
a) Methane
b) Urea
c) Acetic acid
d) Chloroform
Answer: b

Question: Which of the following will have a meso-isomer also?
a) 2-chlorobutane 
b) 2, 3-dichlorobutane
c) 2, 3-dichloropentane
d) 2-hydroxypropanoic acid
Answer: b

Question: The name of the compound

is
a) (2Z, 4Z)-2, 4-hexadiene
b) (2Z, 4E)-2, 4-hexadiene
c) (2E, 4Z)-2, 4-hexadiene
d) (4E, 4Z)-2, 4-hexadiene
(e) (2E, 4E)-2, 4-hexadiene
Answer: a

Question: Geometrical isomerism is shown by 
a) —C—C—
b) C=C
c) — C- C—
d) None of these
Answer: b

Question: What is the IUPAC name of t-butyl alcohol.
a) Butanol–2
b) 2–Methyl-propan–2-ol
c) Butanol–1
d) Propanol-2
Answer: b

Question: IUPAC name of (CH₃)₃ CCl is
a) 1-butyl chloride
b) 3-chloro butane
c) 2-chloro-2-methylpropane
d) 2-butyl chloride
Answer: c

Question: The compound, whose stereo-chemical fommla is written below, exhibits x geometrical isomers and y optical isomers The values of x and y are

a) 4 and 4
b) 2 and 2
c) 2 and 4
d) 4 and 2
Answer: b

Question: The shape of methyl carbanion is similar to that of –
a) BF₃
b) NH₃
c) methyl free radical
d) methyl carbocation
Answer: b