Organic Chemistry – Some Basic Principles and Techniques · Question 37

Structure of the compound whose IUPAC name is 3-Ethyl-2-hydroxy-4-methylhex-3-en-5-ynoic acid is

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

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

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

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

1. sp2
2. spd2
3. sp2d
4. sp3

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

Which of the following chemical system is non aromatic?

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

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

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

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

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

Which of the following species is not electrophilic in nature?

1. Cl
2. BH3
3. H3 O
4. NO2