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Option : (a) Methane

Option : (b) Friedel Craft’s reaction

Correct answer is

(a) Only I

Since, iodine is a better leaving group than chloride 2-iodo-2-methyl butane undergo SN^-1reaction faster than tert-butyl chloride.

Since, 

2-Iodo-2-methyl butane is a tertiary alkyl halide, it undergoes SN^-1 reaction faster than 2-iodo-3-methyl butane.

Since, 

2-chloropropane is a secondary alkyl halide, it undergoes SN^-1 reaction faster than 1-chloropropane.

Correct answer is

b. Swartz reaction

Option : (b) the inversion of configuration

Directive Influence of Halogen atom in Haloarenes:

In haloarenes, the halogen atom present in the ring is ortho and para directing in nature and therefore in a substitution reaction, a mixture of isomeric products is formed, in which the para-isomer is the major product since the para position is less hindered in the molecule of haloarene compared to ortho position.
In haloarenes, the halogen atom has also a strong –I (inductive) effect which is likely to deactivate the ring and the electrophilic attack will become rather difficult. However, +M effect dominates over the –I effect when the electrophile is directed to ortho and para position in the ring. Therefore, the electrophilic substitution takes place at these positions though with difficulty. The electrophilic attack is not feasible at the meta position in the ring because the +M effect is rather weak and –I effect of the halogen atom is expressed to have greater magnitude.

Option : (a) CH₃X

Alkyl halide from halogen exchange:

In this reaction, alkyl halides are prepared from alkyl halides only.
For Example:
R – Cl + Nal \(\overset{\Delta}{\underset{Acetone}{\longrightarrow}}\) R – I + NaCl
R – Br + Nal \(\overset{\Delta}{\underset{Acetone}{\longrightarrow}}\) R – I + NaBr
This reaction is known as the Finkelstein reaction. The synthesis of alkyl fluoride is best accomplished by heating alkyl iodide in the presence of a metallic fluoride such as AgF. This reaction is called “Swarts reaction”.
R – I + AgF → R -F + Agl

Option : (c) Swarts reaction

Option : (a) 3-Bromo-3, 4-dimetbyiheptane

Option : (a) o- and p-di reefing

Option : (d) NaCl

Option : (a) Vinyl chloride

In S_N2 mechanism, a pentacoordinate T.S. is involved. The order of reactivity of alkyl halides towards S_N2 mechanism is. Primary > Secondary > Tertiary, (due to increasing crowding in T.S. from primary to tertiary halides.

1- Chlorobutane being primary halide will react faster by S_N2 mechanism, than the secondary halide 2- chlorobutane.)

Correct answer is

(c) 2-iodo-2 methylbutane

(c) Halogen exchange

The answer is (b) Ethanol

(a) Freon – 11 = CFCl₃
(b) Freon – 12 = CF₂Cl₂
(c) Freon – 111 = C₂FCl₅

(i) It is used as a fire extinguisher.
(ii) It is used in dry cleaning.
(iii) It is used for the manufacture of freon and salicylic acid.
(iv) It is used as a solvent.

(a) Transition state

The answer is (c) CCl₄

Option : (d) 8

Option : (d) All of these

Option : (d) 2-Chloropropane

Option : (c) isopropyl alcohol

• A racemic mixture contains equimolar (or equimolecular) quantities of the dextrorotatory (d-) and laevorotatory (l-) isomers (enantiomers) of a compound. 
• The d-enantiomer rotates the plane of plane-polarized light to the right, while the l-enantiomer rotates the same to the left to the same extent.
• The quantities of the d- and lenantiomers being the same, both the rotations are of the same magnitude, but of opposite directions. Hence, they cancel each other. Hence, a racemic mixture is optically inactive.
• It is represented as dl or (+). Example : ( ± ) lactic acid  

Option : (a) equal amount of d and l isomers

Option : (c) n-propyl iodide

Option : (c) sec-butyl chloride

The number of optical isomers : 16.

The number of optical isomers : 3.

Option : (b) 3° > 2° > 1°

Option : (c) 4

Option : (d) CICH₂ – CH = CH₂

Option : (c) optically inactive

Option : (b) CH₃F < CH₃C1 < CH₃Br < CH₃I

Option : (a) insecticide

Carbon tetrachloride (CCl₄) or tetrachloromethane is used in the fire extinguisher.

(b) chloroform

chloroform is used as source of dichlorocarbene.

Electrophiles: H⁺, \(\overset{+}{N}O_2\), \(\overset{+}{C}l\)

Nucleophiles: \(\overset{-}{O}H\), \(\overset{-}{O}R\), \(\overset{-}{C}l\)

The chemical name of DDT is p, p'- Dichlorodiphenyltrichloroethane.

Option : (b) CH₃ – CH₂ – CH₂ – I

Option : (c) dry cleaning agent

Option : (b) 4

a. Vinyl halide 

b. C – X bond length shorter in vinyl halide than alkyl halide. Vinyl halide has partial double bond character due to resonance.

In vinyl halide, carbon is sp hybridised. The bond is shorter and stronger and the molecule is more stable.

c. Yes, It reacts by S_N1 mechanism. S_N1 mechanism involves formation of carbocation intermediate. The vinylic carbocation intermediate formed is resonance stabilized, hence S_N1 mechanism is favoured.

l-Bromo-2-methylpropane, 2-Bromopropane, 1-Bromopropane, 1-Bromo butane