The concentration of an organic compound in chloroform is $6.15 \mathrm{~g}$ per $100 \mathrm{~mL}$ of…

The concentration of an organic compound in chloroform is $6.15 \mathrm{~g}$ per $100 \mathrm{~mL}$ of solution. A portion of this solution in a $5 \mathrm{~cm}$ polarimeter tube causes an observed rotation of $-1.2^{\circ}$. What is the specific rotation of the compound?
  1. $+12^{\circ}$
  2. $-3.9^{\circ}$
  3. $-39^{\circ}$
  4. $+61.5^{\circ}$

Solution

$\begin{aligned} {[\alpha] } & =\frac{[\alpha]_{\text {observed }}}{l \times C} \\ & =\frac{-1.2}{5 \times \frac{6.15}{1000}}=-39^{\circ}\end{aligned}$

Asked in: AP EAMCET 2009

Practice more General Organic Chemistry questions on Aicharya