Question

Why carbohydrates are generally optically active?

Answer 1

Carbohydrates are generally optically active because they have one or more chiral carbon atoms in their molecules. For example, Glucose has four chiral carbons and therefore it is optically active.

\[\begin{array}{cc}
\ce{CHO}\\
|\phantom{....}\\
\ce{^*CHOH}\\
|\phantom{....}\\
\ce{^*CHOH}\\
|\phantom{....}\\
\ce{^*CHOH}\\
|\phantom{....}\\
\ce{^*CHOH}\\
|\phantom{....}\\
\phantom{...}\ce{CH2OH}
\end{array}\]

\[\ce{^*C}\] - Chiral carbon