NEET Chemistry Organic Chemistry Some Basic Principles and Techniques MCQs Set A

Question: In which of the following homolytic bond fission takes place?

• a) Alkaline hydrolysis of ethylchloride
• b) Addition of HBr to double bond
• c) Photochlorination of methane
• d) Nitration of benzene

Answer: Photochlorination of methane

Question: Which of the following is heterocyclic compound?

• a) Pyrrole
• b) Furan
• c) Thiophene
• d) All of these

Answer: All of these

Question: Which of the following shows structure of neohexane?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: The incorrect match is

• a) C_nH_{2n – 2}   – Alkyne 
• b) C_nH_2n   – Alkene
• c) C_nH_{2n + 2}    – Bicycloalkane 
• d) C_nH_{2n – 2}    – Alkadiene

Answer:  C_nH_{2n + 2}    – Bicycloalkane 

Question: The number of C atoms present in allyl vinyl acetylene is _____ and it has _____ degree of unsaturation

• a) 7 and 4
• b) 7 and 3
• c) 5 and 4
• d) 5 and 3

Answer: 7 and 4

Question:  In the structure

The number of functional groups present is

• a) Two
• b) Four
• c) Five
• d) Three

Answer: Four

Question:  IUPAC name for the compound having formula C(CH₃)₄ is

• a) Tetramethylmethane
• b) 1, 1, 1, 1-Tetramethylmethane
• c) 2, 2-Dimethylpropane
• d) 2, 2-Dimethylisopropane

Answer: 2, 2-Dimethylpropane

Question:  IUPAC name for the compound

• a) 3-Methyl-4-ethylhexane
• b) 3-Ethyl-4-methylhexane
• c) 4-Ethyl-3-methylhexane
• d) Nonane

Answer: 3-Ethyl-4-methylhexane

Question:  IUPAC name of the compound

BrCH₂– CHCl – CHCl₂ is

• a) 1–Bromo–2, 3, 3–trichloropropane
• b) 1,1, 2–Trichloro–3–bromopropane
• c) 3–Bromo–1, 1, 2–trichloropropane
• d) Trichlorobromopropane

Answer: 3–Bromo–1, 1, 2–trichloropropane

Question:  IUPAC name of the compound

• a) Cyclopentylethyne
• b) Ethynylcyclopentane
• c) Cyclopentylacetylene
• d) Ethynylpentane

Answer: Ethynylcyclopentane

Question: The compound which has one isopropyl group is

• a) 2, 2, 3, 3 -Tetramethylpentane
• b) 2, 2 -Dimethyl pentane
• c) 2, 2, 3-Trimethylpentane
• d) 2-Methyl pentane

Answer: 2-Methyl pentane

Question: Which alkane would have only primary and tertiary carbon?

• a) Pentane
• b) 2-Methylbutane
• c) 2, 2-Dimethyl propane
• d) 2, 3-Dimethylbutane

Answer: 2, 3-Dimethylbutane

Question:  The IUPAC name of CH₃–CHBr–CH₂OH is

• a) 3-Hydroxy 2-bromopropane
• b) 2-Bromopropan-1-ol
• c) 2-Bromo 3-propanol
• d) 3-Hydroxy isopropyl bromide

Answer: 2-Bromopropan-1-ol

Question:  The IUPAC name of CH₃OC₂H₅ is

• a) Ethoxymethane
• b) Methoxyethane
• c) Methyl ethyl ether
• d) Ethyl methyl ether

Answer: Methoxyethane

Question:  The IUPAC name of the compound

• a) 1, 2, 3-Cyanopropene
• b) 1, 2, 3-Cyanopropane
• c) 3-Cyanopentan-1, 5,-dinitrile
• d) Propane-1,2,3-tricarbonitrile

Answer: Propane-1,2,3-tricarbonitrile

Question:  The IUPAC name of the following compound

• a) Butandione
• b) 2,3–Butandiketone
• c) Butane–2,3–dione
• d) None of these

Answer: Butane–2,3–dione

Question:  The IUPAC name of

• a) 4,5–Diethylocta–2,4,7–triene
• b) 4,5–Diethylocta–1,4,6–triene
• c) 4,5–Dimethylocta–1,4,6–triene
• d) 4, 5-Diethylocta-1, 4, 6 triyne

Answer: 4,5–Diethylocta–1,4,6–triene

Question:  The IUPAC name of

• a) Pent-2-en-5-yne
• b) Pent-1-en-4-yne
• c) Pent-4-en-1-yne
• d) Pent-4-en-2-yne

Answer: Pent-1-en-4-yne

Question:  IUPAC name of

• a) 2-methoxybenzoic acid
• b) 2-carboxymethoxide
• c) 2-carboxyphenylmethoxide
• d) 2-methoxycarboxybenzene

Answer: 2-methoxybenzoic acid

Question:  The number of tertiary carbon atoms in the following structure is

• a) Four
• b) Three
• c) Two
• d) One

Answer: One

Question:  The IUPAC name of

• a) N, N-dimethylmethanal
• b) N, N-dimethylmethanamide
• c) N, N-dimethylcarbaldehyde
• d) None of these

Answer: N, N-dimethylmethanamide

Question:  The IUPAC name of

• a) 4-methoxy-1-methylchlorobenzene
• b) 2-chloro-1-methoxy-4-methylbenzene
• c) 1-methoxy-2-chloro-4-methylbenzene
• d) 4-methyl-2-chloroanisole

Answer: 2-chloro-1-methoxy-4-methylbenzene

Question:  Which of the following represents the correct order of stability of the given carbocations?

• a) III > I > II
• b) I > III > II
• c) III > II > I
• d) II > III > I

Answer: III > I > II

Question: The number of chain isomers possible in C₅H₁₂ is

• a) 2
• b) 3
• c) 4
• d) 5

Answer: 3

Question:

• a) Functional isomers
• b) Position isomers
• c) Chain isomers
• d) These are not isomers

Answer: These are not isomers

Question:

• a) Chain isomers
• b) Position isomers
• c) Metamers
• d) Functional isomers

Answer: Position isomers

Question:  Number of structural isomers possible in C₃H₆O,are

• a) 9
• b) 6
• c) 5
• d) 3

Answer: 9

Question:

In  most stable radicals/ions formed on homolysis is/are

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: The most stable carbocation is

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: The most stable carbanion is

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: The most stable alkene is

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:

The decreasing order of –I effect is

• a) (I) > (II) > (III)
• b) (I) > (III) > (II)
• c) (III) > (II) > (I)
• d) (III) > (I) > (II)

Answer: (I) > (III) > (II)

Question: Which of the following is not an electrophile?

• a)

  

• b) AlCl₃ 
• c) SiF₄
• d)

  

Answer:

Question:  CH₂ is an

• a) Electrophile
• b) Nucleophile
• c) Free radical
• d) Ambiphiles

Answer: Electrophile

Question: The nucleophile is not

• a) Lewis base
• b) Lewis acid
• c)

  

• d) Carbanion

Answer: Lewis acid

Question: The most stable carbocation is

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:  The number of hyperconjugation structures possible in

• a) 3
• b) 2
• c) 6
• d) None of these

Answer: 3

Question: The electromeric effect is

• a) Permanent effect
• b) Temporary effect
• c) π-electrons transfer in this effect
• d) Both (2) & (3)

Answer: Both (2) & (3)

Question: In  

most stable is

• a) (I)
• b) (II)
• c) Sometimes (I) and sometimes (II)
• d) Both are equal stable

Answer: (I)

Question:

is a/an

• a) Substitution reaction
• b) Elimination reaction
• c) Electrophilic addition reaction
• d) Nucleophilic addition reaction

Answer: Electrophilic addition reaction

Question: Which one is incorrect match of reactions?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:  The correct statement for α-elimination is

• a) It forms cyclic compounds
• b) It forms carbene or substituted carbene
• c) Two atoms are removed from α and β positions 
• d) In CHCl₃; α elimination is not possible

Answer: It forms carbene or substituted carbene

Question:  In compound

The hybridization of C (1) to (7) are

• a) sp², sp², sp², sp, sp², sp, sp 
• b) sp², sp, sp, sp², sp², sp², sp
• c) sp, sp, sp², sp, sp², sp², sp² 
• d) sp², sp, sp², sp, sp³, sp, sp

Answer:  sp², sp², sp², sp, sp², sp, sp 

Question:  The correct order of stability of

• a) (IV) > (III) > (II) > (I)
• b) (I) > (II) > (III) > (IV)
• c) (II) > (I) > (III) > (IV)
• d) (IV) > (II) > (III) > (I)

Answer: (I) > (II) > (III) > (IV)

Question: The hybridization and shape of 

are respectively

• a) sp³ and trigonal pyramidal 
• b) sp³ and tetrahedral
• c) sp³ and trigonal planar
• d) sp² and trigonal planar

Answer:  sp³ and trigonal pyramidal 

Question: The mixture of urea and napthalene can be separated by

• a) Filtration
• b) Sublimation
• c) Chromatographic
• d) Distillation

Answer: Sublimation

Question: Number of C atoms which are present linearly in vinyl acetylene is

• a) 2
• b) 3
• c) 4
• d) 1

Answer: 3

Question: Chloroform and aniline can be purified by

• a) Sublimation
• b) Crystallization
• c) Distillation
• d) Chromatographic

Answer: Distillation

Question: Principle of crystallization method depends on

• a) Solubility difference
• b) Boiling point difference
• c) Refractive index difference
• d) Difference in vapour pressure

Answer: Solubility difference

Question: The principle involved in gas liquid chromatography (GLC) is

• a) Adsorption
• b) Absorption
• c) Partition
• d) Condensation

Answer: Adsorption

Question: Steam distillation is applied for the separation of those compounds which are

• a) Steam volatile and soluble in water
• b) Steam volatile and decompose in water
• c) Steam volatile and insoluble in water
• d) Capable of chemical reaction with steam

Answer: Steam volatile and insoluble in water

Question: The process of differential extraction is based upon

• a) Different solubilities
• b) Different molecular masses
• c) Different boiling points
• d) Different freezing point

Answer: Different solubilities

Question: Glycerol decomposes at its boiling point. The purification of glycerol can be affected by

• a) Crystallisation
• b) Simple distillation
• c) Distillation under reduced pressure
• d) Fractional crystallisation

Answer: Distillation under reduced pressure

Question: Which of the following compound will give blood red colour while doing the Lassaigne’s test for N?

• a) (NH₂)₂C = O 
• b) H₂N (C₆H₄)SO₃H
• c) C₆H₅SO₃H
• d) CHCl₃

Answer: H₂N (C₆H₄)SO₃H

Question:  The violet-red colour in the Lassaigne’s test of sulphur is due to

• a) FeCl₃
• b) Na₂[Fe(CN)₆] 
• c) Na₄[Fe(CN)₅NOS]
• d) None of these

Answer:   Na₄[Fe(CN)₅NOS]

Question: The function of boiling the sodium extract with concentrated nitric acid before testing halogens is

• a) To make solution clear
• b) To destroy CN^– and S^2– ions
• c) To make the solution acidic
• d) To disproportionate CN^– and S^–2

Answer: To destroy CN^– and S^2– ions

Question: A mixture of acetone and methanol can be separated by

• a) Vacuum distillation
• b) Steam distillation
• c) Fractional distillation
• d) Simple distillation

Answer: Fractional distillation

Question: In Duma’s method for determining the nitrogen content of an organic compound, the nitrogen content is determined in the form of

• a) Gaseous NH₃
• b) NaCN
• c) Gaseous N₂
• d) (NH₄)₂SO₄  

Answer:  Gaseous N₂

Question: The Na metal used in "Lassaigne's test" is due to

• a) Formation of ionic compound
• b) Its compounds are soluble in H₂O
• c) Na is reactive metal
• d) All of these

Answer: All of these

Question: If 0.2 g of an organic compound on complete combustion produces 0.18 g of water then % of hydrogen in it is

• a) 5
• b) 10
• c) 1
• d) 20

Answer: 10