Mandelic acid, also known as bitter mandelic acid, is a white rhombic flake crystal. Melting point 119ºC. Soluble in hot water, ether, isopropyl alcohol and ethanol exposed for too long, will cause discoloration and decomposition. It can be prepared by the action of benzaldehyde with acetophenone dibromide. Used in organic synthesis, it is a special reagent for the determination of zirconium.