Question

Assertion: Racemic mixture is optically inactive.

Reason: Racemic mixture is a mixture of meso compounds.

• A. Both Assertion and Reason are false.
• B. Assertion is true, but Reason is false.
• C. Both Assertion and Reason are true. The reason is the correct explanation of Assertion.
• D. Both Assertion and Reason are true. The reason is not the correct explanation of Assertion.

Answer 1

The correct option is B

Assertion is true, but Reason is false.

The explanation for the Assertion statement

• Racemic mixtures are two enantiomers of an optically active substance mixed $50:50$.
• The rotation caused by the molecules of one enantiomer is exactly canceled by the equal and opposite rotation caused by the molecules of the other enantiomers.
• Hence it is always optically inactive.

The explanation for the Reason statement

• A stereoisomer with an identical (superimposable) mirror image is referred to as a meso compound.
• Racemic mixtures and meso compounds are different from each other.
• A meso compound has an identical isomer, whereas a racemic mixture contains non-identical isomers.

Therefore, the correct option is (A) Both Assertion and Reason are false.