Question

An SN2 reaction at an asymmetric carbon of a compound always gives ------? *
• An inversion configuration of the substrate
• An Retention configuration of the substrate
• Racemic Compound
• A mixture of diastereomers​

Answer 1

Answer:

Inversion occurs in SN2 reaction, so a product with opposite optical rotation is obtained. option B is correct

Answer 2

Answer: A

Explanation: in Sn2 reaction inversion of configuration occurs for all molecules. Hence we get a single stereoisomer( racemic mixture and mixture of enantiomer and diastereomers are out of the question).
Inversion occurs in the case of Sn1 reaction as in that a carbocation is formed and reagent can attack from any side.
In this case the reagent attacks from behind the molecule and as it attaches the leaving group slowly detaches. Hence at the end we get a product that has the reagent attached opposite to the original group(inversion)