PYQSide ExamsMy practice

Organic Chemistry – Some Basic Principles and Techniques · Question 43

NEET 2013 (Karnataka)MCQEasy📈 Topic in 25% papers+4−1
1

Which of the following chemical system is non aromatic?

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]

Answer

(4) [figure]

Solution

A ring is aromatic when it is cyclic, planar, completely conjugated (every ring atom sp2) and has (4n+2) π electrons (Hückel's rule).

(1) Benzene ⇒ 6 π electrons (n = 1), fully conjugated ⇒ aromatic.

(2) Naphthalene ⇒ 10 π electrons (n = 2), fully conjugated ⇒ aromatic.

(3) Thiophene ⇒ 4 π electrons of the two C=C bonds + one lone pair of S in conjugation = 6 π electrons ⇒ aromatic.

(4) Cyclopenta-1,3-diene ⇒ the CH2 carbon is sp3, so cyclic conjugation is broken ⇒ non-aromatic.

Answer: (4)

NEET 2013 (Karnataka)

Keep practising — Organic Chemistry – Some Basic Principles and Techniques

2

Which nomenclature is not according to IUPAC system?

  1. Br-CH2-CH=CH2 1-Bromoprop-2-ene
  2. [figure] 4-Bromo-2,4-dimethylhexane
  3. [figure] 2-Methyl-3-phenylpentane
  4. [figure] 5-Oxohexanoic acid
AIPMT 2012 (Prelims)
3

Which one of the following is most reactive towards electrophilic reagent?

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]
AIPMT 2011 (Prelims)
4

The correct IUPAC name for the compound is [figure]

  1. 4-ethyl-3-propylhex-1-ene
  2. 3-ethyl-4-ethenylheptane
  3. 3-ethyl-4-propylhex-5-ene
  4. 3-(1-ethylpropyl)hex-1-ene
AIPMT 2011 (Prelims)
5

Which of the following species is not electrophilic in nature?

  1. Cl
  2. BH3
  3. H3 O
  4. NO2
AIPMT 2010 (Mains)
6

The IUPAC name of the compound CH3CH=CHC CH is

  1. pent-4-yn-2-ene
  2. pent-3-en-1-yne
  3. pent-2-en-4-yne
  4. pent-1-yn-3-ene
AIPMT 2010 (Mains)
7

Which one of the following is most reactive towards electrophilic reagent?

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]
AIPMT 2010 (Prelims)
8

The IUPAC name of the compound having the formula CH C-CH=CH2 is

  1. 1-butyne-3-ene
  2. but-1-yne-3-ene
  3. but-1-en-3-yne
  4. 3-butene-1-yne.
AIPMT 2009
9

The state of hybridisation of C2, C3, C5 and C6 of the hydrocarbon, [figure] is in the following sequence

  1. sp3, sp2, sp2 and sp
  2. sp, sp2, sp2 and sp3
  3. sp, sp2, sp3 and sp2
  4. sp, sp3, sp2 and sp3
AIPMT 2009
10

Base strength of [figure] is in the order of

  1. (i) > (iii) > (ii)
  2. (i) > (ii) > (iii)
  3. (ii) > (i) > (iii)
  4. (iii) > (ii) > (i)
AIPMT 2008
11

Which one of the following is most reactive towards electrophilic attack?

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]
AIPMT 2008

All Organic Chemistry – Some Basic Principles and Techniques PYQs →

PDFDownload Organic Chemistry – Some Basic Principles and Techniques PYQs as PDF Free, with answer key and a QR code to every solution — print it or study offline⬇
All NEET Chemistry chapters
Physical ChemistrySome Basic Concepts of ChemistryStructure of AtomStates of MatterThermodynamicsEquilibriumRedox ReactionsSolid StateSolutionsElectrochemistryChemical KineticsSurface Chemistry
Inorganic ChemistryClassification of Elements and Periodicity in PropertiesChemical Bonding and Molecular StructureHydrogens-Block Elementsp-Block Elements (Group 13 & 14)Environmental ChemistryGeneral Principles of Isolation of Elementsp-Block Elements (Group 15–18)d- and f-Block ElementsCoordination Compounds
Organic ChemistryOrganic Chemistry – Some Basic Principles and TechniquesIsomerismHydrocarbonsHaloalkanes and HaloarenesAlcohols, Phenols and EthersAldehydes, Ketones and Carboxylic AcidsAminesBiomoleculesPolymersChemistry in Everyday LifePrinciples Related to Practical Chemistry