question_answer

The enantiomeric excess and observed specific rotation of a mixture containing 6 gm of \[(+)-2-\]butanol and 4 (gm) of \[(-)-2-\]butanol are respectively (If the specific rotation of enantiomerically pure \[(+)-2-\]butanol is\[+\,13.5\,\text{unit}\]).

A) 80%, \[+\,2.7\,\text{unit}\]

B) 20%, \[-\,27\,\text{unit}\]

C) 20%, \[+\,2.7\,\text{unit}\]

D) 80%, \[-\,27\,\text{unit}\]

Correct Answer: C

Solution :

\[\times 100=\frac{6-4}{6+4}\times 100=20%\]