Among the following statements, choose the correct statements.

A. S_N2 reaction proceeds with stereochemical inversion.

B. The process of conversion of Racemic mixture into two enantiomers is known as Racemization.

C. A mixture containing 2 enantiomers in equal proportions is known as Racemic mixture.

D. The stereoisomers related to each other as superimposable on their mirror image are called enantiomers.

E. The objects which are non-superimposable on their mirror image are said to be chiral and this property is known as chirality.

A, C, and E only

A. S_N2 reaction proceeds with stereochemical inversion. 

A bimolecular nucleophilic substitution (S_N2) reaction is a type of nucleophilic substitution whereby a lone pair of electrons on a nucleophile attacks an electron-deficient electrophilic center and bonds to it, resulting in the expulsion of a leaving group. It is possible for the nucleophile to attack the electrophilic center in two ways.

   Frontside Attack:  In a frontside attack, the nucleophile attacks the electrophilic center on the same side as the leaving group. When a frontside attack occurs, the stereochemistry of the product remains the same; that is, we have retention of configuration.

   Backside Attack: In a backside attack, the nucleophile attacks the electrophilic center on the side that is opposite to the leaving group. When a backside attack occurs, the stereochemistry of the product does not stay the same. There is inversion of configuration.

The following diagram illustrates these two types of nucleophilic attacks, where the frontside attack results in retention of configuration; that is, the product has the same configuration as the substrate. The backside attack results in inversion of configuration, where the product's configuration is opposite that of the substrate.

C.  A mixture containing two enantiomers in equal proportions will have zero optical rotation, as the rotation due to one isomer will be canceled by the rotation due to the other isomer. Such a mixture is known as a racemic mixture or racemic modification.

E. Objects which are non-superimposable in their mirror images are called chiral and the property of non-superimposability is called chirality while those which are superimposable on their mirror images are called achiral.