Question

A solution of $\left(R\right)-2-$iodobutane, $\left[\alpha \right]={15.9}^{\circ }$ in acetone is treated with radioactive iodied, until $1.0$% of iodobutane contain radioactive iodine, the specific rotation of recovered iodobutane is found to be $-{15.58}^{\circ },$ which statement is correct about above information?

• A. It has optical purity $96$%
• B. % of R in solution is $99$%
• C. Racemic mixture is $2$%
• D. Final solution is dextrorotatory

Answer 1

Answer: (B), (C)

The correct options are
B % of R in solution is $99$%
C Racemic mixture is $2$%

% of $R$ in solution is $100-\frac{15.58}{15.9}=99$%
Racemic mixture is $\frac{15.9-15.58}{15.58}\times 100=2$%