Hydriodic Acid

(hi-dre-od'ik-.) (Chem.) A colorle gas composed of equal volumes of hydrogen and iodine vapor. It is rapidly absorbed by water, forming an aqueous solution, which fumes strongly in the air, and po e es powerful acid properties. On exposure to the air it decomposes with absorption of oxygen and separation of free iodine. In its chemical properties it is somewhat similar to hydrochloric acid. Sp. gr. 4-435; Form. HI. [s. 469]