Question

The specific rotation [α] of (1S, 2R)-ephedrine HCl salt in water is −32.5° at 22 °C (light source: sodium D line). What is the optical rotation α in degrees (°) of an aqueous solution containing 250 mg/mL (1R, 2S)-ephedrine HCl salt AND 50 mg/mL (1S, 2R)-ephedrine HCl salt measured using a 1.00-cm pathlength tube under the same condition?

Answer 1

Specific ratation[a] = Here, α is optical rotation in degrees, l is path length, and c is the concentration in g/mL Specific rat ation(a)-- xc 10g 1 0.1dm 1cm Ime ML =-0.813。 Specific rat ation(a)-- xc 103g1 1cm --0.163