PYQSide ExamsMy practice

Organic Chemistry – Some Basic Principles and Techniques · Question 39

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

The outer orbitals of C in ethene molecule can be considered to be hybridized to give three equivalent sp2 orbitals. The total number of sigma (σ) and pi (π) bonds in ethene molecule is

  1. 3 sigma (σ) and 2 pi (π) bonds
  2. 4 sigma (σ) and 1 pi (π) bonds
  3. 5 sigma (σ) and 1 pi (π) bonds
  4. 1 sigma (σ) and 2 pi (π) bonds

Answer

(3) 5 sigma (σ) and 1 pi (π) bonds

Solution

Ethene: CH2=CH2

σ bonds: 4 C–H + 1 C–C = 5

π bonds: 1 (in the C=C double bond, from sideways overlap of unhybridised 2p orbitals)

∴ 5 σ and 1 π bonds

Answer: (3)

NEET 2013 (Karnataka)

Keep practising — Organic Chemistry – Some Basic Principles and Techniques

2

Arrange the following in increasing order of stability 1. (CH3)2- C-CH2-CH3 2. (CH3)3- C 3. (CH3)2- CH 4. CH3- CH2 5. CH3

  1. 5 < 4 < 3 < 1 < 2
  2. 4 < 5 < 3 < 1 < 2
  3. 1 < 5 < 4 < 3 < 2
  4. 5 < 4 < 3 < 2 < 1
NEET 2013 (Karnataka)
3

What is the hybridisation state of benzyl carbonium ion? [figure]

  1. sp2
  2. spd2
  3. sp2d
  4. sp3
NEET 2013 (Karnataka)
4

Homolytic fission of the following alkanes forms free radicals CH3-CH3, CH3-CH2-CH3, (CH3)2CH-CH3, CH3-CH2-CH(CH3)2. Increasing order of stability of the radicals is

  1. (CH3)2 C-CH2CH3 < CH3- CH-CH3 < CH3- CH2 < (CH3)3 C
  2. CH3- CH2 < CH3- CH-CH3 < (CH3)2 C-CH2-CH3 < (CH3)3 C
  3. CH3- CH2 < CH3- CH-CH3 < (CH3)3 C < (CH3)2 C-CH2CH3
  4. (CH3)3 C < (CH3)2 C-CH2CH3 < CH3- CH-CH3 < CH3- CH2
NEET 2013 (Karnataka)
5

Which of the following chemical system is non aromatic?

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]
NEET 2013 (Karnataka)
6

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)
7

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

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]
AIPMT 2011 (Prelims)
8

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)
9

Which of the following species is not electrophilic in nature?

  1. Cl
  2. BH3
  3. H3 O
  4. NO2
AIPMT 2010 (Mains)
10

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)
11

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

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

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