Q1. Quinine or its salts give no color with Erdmann's reagent, Fröhde's reagent, or with concentrated nitric acid (difference from morphine).

Q2. Solutions of quinine, as well as many salts of quinine, after acidifying with sulfuric add, give a bluish fluorescence, perceptible in very dilute solutions and a characteristic reaction. Concentrated acid dissolves the dry alkaloid to a similar fluid, with no brown or black color.  If the solution in sulfuric acid is exactly neutralized with ammonia, one drop of hydrogen peroxide and one of copper sulfate solution added, then boiled, an intensely red color appears, changing slowly to blue, and finally green.

Q3. Ten cc of a solution of a quinine salt in water with two drops of bromine water or chlorine water and enough am-monium hydroxide to render it alkaline gives an emerald-green color, a characteristic reaction.

Q4. If to an alcoholic solution of quinine sulfate there is added tincture of iodine, and the mixture is warmed, then allowed to stand and cool, there separates a precipitate con-sisting of clusters of crystals, dark green by transmitted light and with a metallic luster by reflected light. The compound is called herapathite, and is characteristic of quinine.