The stereoisomers related to each other as non-superimposable mirror images are called enantiomers. Enantiomers possess identical physical properties namely, melting point, boiling point, refractive index, etc. They only differ with respect to the rotation of plane polarised light. If one of the enantiomers is dextrorotatory, the other will be laevorotatory. Consider the following example:

What are Enantiomers?

The stereoisomers which are related to each other as non-superimposable mirror images are known as enantiomers. Enantiomers have similar physical properties such as boiling point, melting point, refractive index, etc. They only differ w.r.t the rotation of plane-polarized light. If one of the enantiomers is levorotatory, the other will be dextrorotatory. The compounds A and B in the following image are enantiomers.

Explain why alkyl halides, though polar, are immiscible with water?

To be miscible with water, the solute-water force of attraction must be stronger than the solute-solute and water-water forces of attraction. Alkyl halides are polar molecules and so held together by dipole-dipole interactions. Similarly, strong -bonds exist between the water molecules. The new force of attraction between the alkyl halides and water molecules is weaker than the alkyl halide-alkyl halide and water-water forces of attraction. Hence, alkyl halides (though polar) are immiscible with water.

E M B I B E

Intermediate Second Year Chemistry>Chapter 11 - Haloalkanes and Haloarenes>Questions>Q 24

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12th Andhra Pradesh Board

IMPORTANT

Earn 100

Explain why allylic and benzylic halides are more reactive than $S_{N}^{1}$ substitution while 1-halo and 2-halobutanes preferentially undergoes $S_{N}^{2}$ substitution.

Important Questions on Haloalkanes and Haloarenes

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12th Andhra Pradesh Board

IMPORTANT

Intermediate Second Year Chemistry>Chapter 11 - Haloalkanes and Haloarenes>Questions>Q 25

Describe the stereochemical effect on the hydrolysis of 2-bromobutane.

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12th Andhra Pradesh Board

IMPORTANT

Intermediate Second Year Chemistry>Chapter 11 - Haloalkanes and Haloarenes>Questions>Q 26

What is the criteria for optical activity? Give two examples of chiral molecules.

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12th Andhra Pradesh Board

IMPORTANT

Intermediate Second Year Chemistry>Chapter 11 - Haloalkanes and Haloarenes>Questions>Q 27

Define racemic mixture.

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12th Andhra Pradesh Board

IMPORTANT

Intermediate Second Year Chemistry>Chapter 11 - Haloalkanes and Haloarenes>Questions>Q 27

Define retention of configuration.

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12th Andhra Pradesh Board

IMPORTANT

Intermediate Second Year Chemistry>Chapter 11 - Haloalkanes and Haloarenes>Questions>Q 27

Define Enantiomers.

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12th Andhra Pradesh Board

IMPORTANT

Intermediate Second Year Chemistry>Chapter 11 - Haloalkanes and Haloarenes>Questions>Q 28

Write the mechanism of dehydrohalogenation of 2-bromobutane.

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12th Andhra Pradesh Board

IMPORTANT

Intermediate Second Year Chemistry>Chapter 11 - Haloalkanes and Haloarenes>Questions>Q 29

Explain the Grignard's reagent preparation and application with example.

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12th Andhra Pradesh Board

IMPORTANT

Intermediate Second Year Chemistry>Chapter 11 - Haloalkanes and Haloarenes>Questions>Q 30

A primary alkyl halide

C_{4} H_{9} Br

(A) reacted with alcoholic

KOH

to give compound (B), Compound (B) is reacted with

HBr

to give (C) which is an isomer of (A). When (A) is reacted with sodium metal it gives compound (D),

C_{8} H_{18}

which is different from the compound formed when n-butyl bromide is reacted with sodium. Give the structural formula of (A) and write the equations for all the reactions.