Question

The specific rotation of the compound (A) is $+X^o$.

Which of the following statement is true?

• A. Specific rotation of enantiomer of A is zero
• B. Specific rotation of enantiomer of A is $+X^o$
• C. Specific rotation of enantiomer of A is $-X^o$
• D. Cannot be determined

Answer 1

The correct option is C Specific rotation of enantiomer of A is $-X^o$

Enantiomers are non-superimposable mirror images. They are related by the rotation of plane polarised light.
They are differentiated by the direction in which they rotate the plane polarised light. Enantiomers rotate plane polarised light at same extent but in opposite direction.

Since, specific rotation of compound 'A' is $+X^o$, its enantiomers will have the value of $-X^o$