Answer: The required [a] for slotion will be -62.7
Explanation:
The specific rotation of pure quinine= -165
% of pure quinine= 69%
% of its enantiomer=ee=31%
Enantiomer excess =(ee)=excess of a single enantiomer/entire mixture×100
Now,
Excess of a single enantiomer=69% - 31%=38%
Entire mixture=69% + 31%= 100%
(ee)=38/100 × 100
=38%
Net rotation= 0.69-0.31=0.38
Hence, [a] for solution will be = -0.38×165= -62.7
