Question

Optical activity of an enantiomeric mixture is +12.6° and the specific rotation of (+) isomer is +30°. The optical purity is ______ %.

Options

• 30

• 25

• 42

• 50

Answer 1

Optical activity of an enantiomeric mixture is +12.6° and the specific rotation of (+) isomer is +30°. The optical purity is 42%.

Explanation:

% optical purity = `"optical rotation of mixture"/"optical rotation of pure enantiomer" xx 100`

`= (12.6^circ)/(30^circ) xx 100`

= 42